Hazard Plain Preview: automated baseline

Gwinnett County, GA

Risk-assessment baseline packet

Unit
County area 13135
Release
2026-10
As of
2026-09-28
Storm Events data through
2026-06-30

Hazard Plain is an independent product built from public federal data, not a FEMA document, and not reviewed or endorsed by FEMA or GEMA/HS; GEMA template letters are a cross-reference only.

A starting point for the plan's risk assessment (FEMA Local Mitigation Plan Review Tool, Element B). It does not replace local data or FEMA review. Section headings say which FEMA review item each table supports; whether an item is satisfied is decided by the plan and its reviewers.

Hazard Plain release 2026-10, as of 2026-09-28. Independent product; not a FEMA document.

Plan clock

Status
Approved, expires 2030-08-07
Plan
Gwinnett County (FEMA plan 111013)
Approved
2025-08-08
Expires
2030-08-07
As of
2026-09-28
Days
1,409 days to expiry

What changed since your last plan (approved 2025-08-08)

New federal declarations
EM-3642-GA (1 declaration row; 1 counted incident)
Storm Events records since approval
6 (data through 2026-06-30)
Repetitive loss now
FMA RL 2, SRL 6 (44 CFR 77.2); any definition: 35
Repeat-flood change
First release: no prior release to compare.

Sources

FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-26T121003Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)

FEMA, OpenFEMA DisasterDeclarationsSummaries v2, version 2026-09-27T010817Z, pulled 2026-09-28, https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries (API)

NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/

FEMA, OpenFEMA NfipMultipleLossProperties v1, version 2026-08-04T164045Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/NfipMultipleLossProperties (API)

Plan status for every jurisdiction listed in this county: 17 rows, in the section "Plan clock: Plan status for every jurisdiction listed in this county" after these cover pages.

State plan status and tribal plans in this state: see the state page.

Plan clock

Plan status for every jurisdiction listed in this county

JurisdictionTypeStatusPlanApprovedExpiresDays to expirynegative = days since expiryUpdate underwayNotes
Gwinnett County (unincorporated area)UnincorporatedApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Auburn cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409FEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.
Berkeley Lake cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Braselton townTownApproved, expires 2031-07-23Jackson County (FEMA plan 110862)2026-07-242031-07-231,759FEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan. Also approved under plan 108611 (Hall County, expires 2028-03-07); plan 111013 (Gwinnett County, expires 2030-08-07). FEMA's plan status map shows one plan per jurisdiction and may show one of these; this packet uses the approved plan that expires last.
Buford cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409Also approved under plan 108611 (Hall County, expires 2028-03-07). FEMA's plan status map shows one plan per jurisdiction and may show one of these; this packet uses the approved plan that expires last.
Dacula cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Duluth cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Grayson cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Lawrenceville cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Lilburn cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Loganville cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409FEMA tracker shows a plan approvable pending adoptionNot yet eligible: adopt the approved plan.
Norcross cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Peachtree Corners cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Snellville cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Sugar Hill cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
Suwanee cityCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409
MulberryCityApproved, expires 2030-08-07Gwinnett County (FEMA plan 111013)2025-08-082030-08-071,409

Source

FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-26T121003Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)

Supports B1-a: hazards GEMA template A: Hazard identification

Hazards NRI does not cover: check locally

  • dam failure (incl. upstream dams)
  • levee failure
  • flash flood as its own subtype
  • ice jams
  • debris flows
  • erosion (riverine and coastal)
  • land subsidence and sinkholes
  • expansive soils

The 18 National Risk Index hazards, ranked by expected annual loss (EAL)

Rank by EALHazardNRI risk ratingEAL ratingEAL buildingsmodeled dollars per yearEAL agriculturemodeled dollars per yearEAL population equivalencestatistical value of life and injury, $13.7M per life, not property damageEAL total (see note)modeled dollars per yearStorm Events records since 1996countEvidence for an omissionNRI Not Applicable, no declaration and no Storm Events record since 1996Storm Events coverage note
1Inland FloodingRelatively HighRelatively High$144,327,787$6,417$528,292$144,862,49645
2TornadoRelatively HighRelatively High$16,233,991$616$6,949,728$23,184,3354
3Cold WaveRelatively HighRelatively High$116,183$16,300$10,792,918$10,925,40214Includes 1 Frost/Freeze record, event types the NRI definition of this hazard leaves out.
4EarthquakeRelatively ModerateRelatively Moderate$8,454,879$2,010,367$10,465,246Not in Storm Events. Storm Events coverage of this hazard is limited; absence is not evidence of low risk.
5HailRelatively HighRelatively High$6,689,033$49$175,922$6,865,003170
6Heat WaveRelatively ModerateRelatively Moderate$301$40$4,868,268$4,868,60911
7LightningVery HighVery High$869,489$3,534,238$4,403,727129
8Strong WindRelatively HighRelatively High$725,386$44$2,067,685$2,793,115286Includes 5 High Wind records and 16 Strong Wind records, event types the NRI definition of this hazard leaves out.
9Ice StormRelatively HighVery High$1,865,346$14,829$1,880,1767
10HurricaneRelatively LowRelatively Low$730,589$7,372$39,171$777,13217
11DroughtRelatively LowRelatively Low$249,036$249,03642
12Winter WeatherRelatively ModerateRelatively Moderate$111,330$30$42,248$153,60837
13WildfireVery LowVery Low$35,011$2$7,210$42,2230No recorded events in Storm Events since 1996 (data through 2026-06-30). Storm Events coverage of this hazard is limited; absence is not evidence of low risk.
14LandslideRelatively LowRelatively Low$15,953$543$16,4970No recorded events in Storm Events since 1996 (data through 2026-06-30). Storm Events coverage of this hazard is limited; absence is not evidence of low risk.
AvalancheNot ApplicableNot Applicable0NRI rates avalanche Not Applicable for this county, and no federal declaration for this county names it.No recorded events in Storm Events since 1996 (data through 2026-06-30).
Coastal FloodingNot ApplicableNot Applicable0NRI rates coastal flooding Not Applicable for this county, and no federal declaration for this county names it.No recorded events in Storm Events since 1996 (data through 2026-06-30).
TsunamiNot ApplicableNot Applicable0NRI rates tsunami Not Applicable for this county, and no federal declaration for this county names it.No recorded events in Storm Events since 1996 (data through 2026-06-30). Storm Events coverage of this hazard is limited; absence is not evidence of low risk.
Volcanic ActivityNot ApplicableNot Applicable0NRI rates volcanic activity Not Applicable for this county, and no federal declaration for this county names it.No recorded events in Storm Events since 1996 (data through 2026-06-30). Storm Events coverage of this hazard is limited; absence is not evidence of low risk.

Total = buildings + agriculture + population equivalence; FEMA values each expected death (or 10 injuries) at $13.7 million (2024 dollars).

Sources

FEMA, FEMA National Risk Index 1.20.0 (December 2025), county and census tract tables, version 1.20.0, pulled 2026-09-28, https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_Counties.zip (download, 25 MB), https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_CensusTracts.zip (download, 635 MB)

NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/

Check your state hazard mitigation plan's hazard list for this county; explain any hazard you drop.

Supports B1-b: location GEMA template B: Hazard profile (events and probability)

Where each hazard occurs

HazardLocationCensus tracts ratedrated of all tracts
AvalancheCensus tract rating counts from the National Risk Index tract table (see B1-f). Tract maps and place names are not in this packet.0 of 220
Coastal FloodingCensus tract rating counts from the National Risk Index tract table (see B1-f). Tract maps and place names are not in this packet.0 of 220
Cold WaveAffects the whole planning area; national data do not distinguish locations within the county. Confirm locally.220 of 220
DroughtAffects the whole planning area; national data do not distinguish locations within the county. Confirm locally.1 of 220
EarthquakeCensus tract rating counts from the National Risk Index tract table (see B1-f). Tract maps and place names are not in this packet.220 of 220
HailAffects the whole planning area; national data do not distinguish locations within the county. Confirm locally.220 of 220
Heat WaveAffects the whole planning area; national data do not distinguish locations within the county. Confirm locally.220 of 220
HurricaneCensus tract rating counts from the National Risk Index tract table (see B1-f). Tract maps and place names are not in this packet.220 of 220
Ice StormAffects the whole planning area; national data do not distinguish locations within the county. Confirm locally.220 of 220
Inland FloodingThe FEMA Flood Insurance Rate Map (FIRM) is the required location source for flooding. See the FEMA Flood Map Service Center (https://msc.fema.gov) for this county.220 of 220
LandslideCensus tract rating counts from the National Risk Index tract table (see B1-f). Tract maps and place names are not in this packet.220 of 220
LightningAffects the whole planning area; national data do not distinguish locations within the county. Confirm locally.220 of 220
Strong WindAffects the whole planning area; national data do not distinguish locations within the county. Confirm locally.220 of 220
TornadoCensus tract rating counts from the National Risk Index tract table (see B1-f). Tract maps and place names are not in this packet.220 of 220
TsunamiCensus tract rating counts from the National Risk Index tract table (see B1-f). Tract maps and place names are not in this packet.0 of 220
Volcanic ActivityCensus tract rating counts from the National Risk Index tract table (see B1-f). Tract maps and place names are not in this packet.0 of 220
WildfireCensus tract rating counts from the National Risk Index tract table (see B1-f). Tract maps and place names are not in this packet.219 of 220
Winter WeatherAffects the whole planning area; national data do not distinguish locations within the county. Confirm locally.220 of 220

Source

FEMA, FEMA National Risk Index 1.20.0 (December 2025), county and census tract tables, version 1.20.0, pulled 2026-09-28, https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_Counties.zip (download, 25 MB), https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_CensusTracts.zip (download, 635 MB)

Supports B1-c: extent GEMA template B: Hazard profile (events and probability)

Extent: scale, observed range and worst recorded event per hazard

HazardScaleRecordscount, yearsObserved rangeWorst recorded eventMost damaging (when different)How it applies to membersNote
Avalanchenone (count and damage)0Physical measure: in event narratives only; local data required.
Coastal Flood, Storm Surge/Tidenone in data (FIRM for depth)0Flood depth: see the FEMA Flood Insurance Rate Map.
Cold/Wind Chill, Extreme Cold/Wind Chillwind chill13, 1996 to 2003 (13 zone-level)1 day to 31 days (median 4 days); 10 with a recorded value31 days, 2000-12-01 to 2000-12-31, from 1 monthly summary record (a monthly summary record covers most or all of a month; it does not count days at wave conditions), zone-levelZone-level records: applies countywide; national data do not locate these events within the county.Wind chill: in event narratives only; local data required. Cold/Wind Chill records from May to September (a frost night, not a cold wave) are counted but not used for the longest run.
Frost/Freeze (outside NRI Cold Wave definition)crop damage1, 2007 to 2007 (1 zone-level)No crop damage reported in 1 records.Zone-level records: applies countywide; national data do not locate these events within the county.Temperature: in event narratives only; local data required.
DroughtUS Drought Monitor D-scale42, 1997 to 2026 (42 zone-level)21 days to 334 days (median 31 days); 19 with a recorded value334 days (11 months), 2016-06-01 to 2017-04-30, a run of 11 consecutive Storm Events drought records, zone-levelDrought, 2000-06-01, property not reported; $1,360,000 crops, reported for the zone (2000 dollars)Zone-level records: applies countywide; national data do not locate these events within the county.Storm Events enters a drought at D2 or worse east of the Rockies and D3 or worse from the Rockies west (NWS Instruction 10-1605); NRI drought counts D3 and D4 only.
EarthquakeModified Mercalli (local data)0No Storm Events record; local data required (e.g., USGS).
Hailhail size (inches)190, 1963 to 20250.75 in to 2.75 in (median 1 in); 190 with a recorded value2.75 in hail, 1998-05-07; same size also recorded on 1997-04-22Hail, 2005-02-21, $5,000,000 property; crops not reported (2005 dollars)Event records naming member places: Duluth city (28 records), Lawrenceville city (28 records), Norcross city (25 records), Dacula city (20 records), Buford city (18 records), Snellville city (18 records), Lilburn city (17 records), Suwanee city (11 records), Sugar Hill city (7 records), Grayson city (6 records); and 1 more member place (see the XLSX file).
Excessive Heat, Heatheat index (narratives)11, 1999 to 2012 (11 zone-level)3 days to 33 days (median 10 days); 5 with a recorded value33 days, 1999-07-20 to 1999-08-21, from 2 records, 1 of them a monthly summary (a monthly summary record covers most or all of a month; it does not count days at wave conditions), zone-levelZone-level records: applies countywide; national data do not locate these events within the county.Heat index: in event narratives only; local data required. Heat records from November to March (unseasonable warmth, not a heat wave) are counted but not used for the longest run.
Hurricane, Tropical Storm, Tropical DepressionSaffir-Simpson17, 2002 to 2024 (17 zone-level)Strongest recorded (records with damage, a wind speed or direct casualties first, then storm type, category and wind): Tropical Storm record, 2017-09-11, $3,000,000 property; crops not reported, reported for the zone (2017 dollars); NWS zone GAZ034 (GWINNETT), zone-level: may include parts of neighboring countiesZone-level records: applies countywide; national data do not locate these events within the county.Storm Events files every zone of a storm's episode under the storm's event type and category, so a Hurricane (Typhoon) record, especially an inland or remnant one, does not by itself mean hurricane-force winds here; read the damage and wind columns.
Ice StormSperry-Piltz (local data)7, 2000 to 2026 (7 zone-level)Ice Storm, 2000-01-22, $980,000 property; crops not reported, reported for the zone (2000 dollars); NWS zone GAZ034 (GWINNETT), zone-level: may include parts of neighboring countiesZone-level records: applies countywide; national data do not locate these events within the county.Ice thickness: in event narratives only; local data required.
Flash Flood, Flood, Lakeshore Flooddamage and flood days (FIRM for depth)45, 1998 to 2023 (2 zone-level)Flood, 2009-09-21, $12,500,000 property; $0 crops (2009 dollars)Event records naming member places: Norcross city (8 records), Duluth city (7 records), Dacula city (3 records), Grayson city (3 records), Suwanee city (3 records), Buford city (2 records), Lilburn city (2 records), Sugar Hill city (2 records), Berkeley Lake city (1 record), Lawrenceville city (1 record). Zone-level records (2) apply countywide.Flood depth: see the FEMA Flood Insurance Rate Map. Storm Events damage can be $0 or blank even for a major flood, so the worst record here may not be the worst flood; compare FEMA Public Assistance by declaration in B1-d.
Debris Flownone (count and damage)0Physical measure: in event narratives only; local data required.
Lightningannualized frequency (the measure FEMA's Local Mitigation Planning Handbook names)129, 1997 to 2022Lightning, 2004-06-27, $50,000 property; crops not reported (2004 dollars), 3 direct deaths, 6 direct injuriesLightning, 2000-09-21, $625,000 property; crops not reported (2000 dollars)Event records naming member places: Lawrenceville city (22 records), Lilburn city (13 records), Dacula city (11 records), Duluth city (11 records), Snellville city (10 records), Buford city (9 records), Suwanee city (9 records), Norcross city (7 records), Grayson city (4 records), Sugar Hill city (4 records); and 1 more member place (see the XLSX file).Storm Events lists lightning with damage or casualties; physical measure in event narratives only; local data required.
High Wind and Strong Wind (outside NRI Strong Wind definition)wind speed (kt and mph)21, 1998 to 2022 (21 zone-level)25 kt (29 mph) to 50 kt (58 mph) (median 39 kt (45 mph)); 16 with a recorded value50 kt (58 mph) estimated gust, High Wind, 2009-04-13, 1 direct injury (reported for the zone); same speed and measurement basis also recorded on 2004-09-16; NWS zone GAZ034 (GWINNETT), zone-level: may include parts of neighboring countiesHigh Wind, 2004-09-16, $750,000 property; crops not reported, reported for the zone (2004 dollars)Zone-level records: applies countywide; national data do not locate these events within the county.
Thunderstorm Windwind speed (kt and mph)327, 1956 to 202532 kt (37 mph) to 78 kt (90 mph) (median 50 kt (58 mph)); 231 with a recorded value78 kt (90 mph) estimated gust, Thunderstorm Wind, 2018-06-01Thunderstorm Wind, 2008-02-26, $1,000,000 property; $0 crops (2008 dollars)Event records naming member places: Norcross city (31 records), Lilburn city (30 records), Lawrenceville city (29 records), Duluth city (22 records), Snellville city (20 records), Buford city (17 records), Suwanee city (17 records), Grayson city (16 records), Dacula city (14 records), Berkeley Lake city (12 records); and 1 more member place (see the XLSX file).
TornadoEnhanced Fujita (F before Feb 2007)12, 1961 to 2020F/EF0 to F/EF2 (median between F/EF1 and F/EF2); 12 with a recorded valueF2 tornado, 1998-04-08, 15 mi within this county, 800 yd wide, $50,000,000 property; crops not reported (1998 dollars), 10 direct injuriesEvent records naming member places: Lawrenceville city (2 records), Grayson city (1 record), Norcross city (1 record).From 1996 on, tornado records are per-county segments and length is the path length within this county (NWS Instruction 10-1605); records before 1996 may give the whole path length, including the path outside this county, and before 1996 a tornado is listed once, under the county where it began, with the whole path's rating; counties farther along the path may not list it. Length is not used to rank tornadoes.
Tsunaminone (count and damage)0Physical measure: in event narratives only; local data required.
Volcanic Ash, Volcanic AshfallVolcanic Explosivity Index (local data)0Physical measure: in event narratives only; local data required.
Wildfireacres burned (local data)0Acres burned: in event narratives only; local data required.
Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleetnone in data (snowfall local)37, 1999 to 2026 (37 zone-level)Winter Storm, 2005-01-28, $350,000 property; crops not reported, reported for the zone (2005 dollars); NWS zone GAZ034 (GWINNETT), zone-level: may include parts of neighboring countiesZone-level records: applies countywide; national data do not locate these events within the county.Snow depth: in event narratives only; local data required.

Where a hazard names more than 10 member places, the table lists the 10 with the most records; every place is in the XLSX file, sheet "B1-c Extent".

Storm Events records are more complete after 1996; before 1996 only Tornado (from 1950), Hail and Thunderstorm Wind (from 1955) exist. Zone-level records are placed with NWS zone-county files, which exist from 2020 on; an earlier record is placed by its zone number in the nearest later file only when its zone name matches that file, records from zones NWS renumbered are placed by name or left out, and a record whose zone is in no known file is left out of every count, so counts before 2020 can be low. Some current zones are also missing from the NWS files, so recent counts can be low too.

Dollars are nominal (as reported), labeled with the year; not adjusted for inflation.

Sources

NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/

NOAA National Weather Service, NWS county-public forecast zones correlation file, version bp03mr20 to bp16ap26 (11 files; newest bp16ap26), pulled 2026-09-28, https://www.weather.gov/gis/ZoneCounty

Supports B1-d: previous occurrences GEMA template B: Hazard profile (events and probability)

Declaration rows
14
Counted incidents
10

Federal disaster declarations for this county

DeclaredIncident beganFEMA numberTypeTitleMapped hazardCounty Public Assistancefederal share obligated, nominal dollarsFlagsNotes
2026-01-242026-01-22EM-3642-GAEmergencySEVERE WINTER STORMWinter Weathernone foundnew since last plan; within last 5 years
2024-09-262024-09-24EM-3616-GAEmergencyHURRICANE HELENEHurricanenone foundduring plan review, check whether your last plan included it; within last 5 years
2020-03-292020-01-20DR-4501-GAMajor disasterCOVID-19 PANDEMICNon-natural, not counted$241,520.41
2020-03-132020-01-20EM-3464-GAEmergencyCOVID-19Non-natural, not countednone foundsame incident as DR-4501
2017-09-152017-09-07DR-4338-GAMajor disasterHURRICANE IRMAHurricane$2,153,618.99
2017-09-082017-09-07EM-3387-GAEmergencyHURRICANE IRMAHurricanenone foundsame incident as DR-4338
2014-02-112014-02-10EM-3368-GAEmergencySEVERE WINTER STORMIce Stormnone found
2009-09-242009-09-18DR-1858-GAMajor disasterSEVERE STORMS AND FLOODINGInland Flooding$9,344,984.05
2005-09-052005-08-27EM-3218-GAEmergencyHURRICANE KATRINA EVACUATIONHurricane: evacuation support, not a local hazard event; not counted$289,660.23
2000-01-282000-01-22DR-1311-GAMajor disasterSEVERE WINTER STORMWinter Weather$3,154,247.57
1998-03-111998-02-14DR-1209-GAMajor disasterSEVERE STORMS AND FLOODINGInland Floodingnone found
1995-10-101995-10-04DR-1071-GAMajor disasterHURRICANE OPALHurricanePA not declared for this county
1993-03-151993-03-13EM-3097-GAEmergencySEVERE SNOWFALL, WINTER STORMWinter Weathernone found
1977-07-201977-07-20EM-3044-GAEmergencyDROUGHTDroughtnone found

County Public Assistance: applicants the FEMA record places in this county, including any state agencies FEMA files there; statewide rows are listed on the state page; federal share obligated, nominal dollars.

Dollars are nominal (as reported), labeled with the year; not adjusted for inflation.

Statewide declarations

DeclaredIncident beganFEMA numberTypeTitleMapped hazardFlagsNotes
1964-11-041964-11-04DR-180-GAMajor disasterFLOODINGInland Flooding
1964-09-101964-09-10DR-177-GAMajor disasterHURRICANE DORAHurricane (primary); also designated: Inland Flooding
1963-03-261963-03-26DR-150-GAMajor disasterSEVERE STORMS & FLOODINGInland Flooding
1961-03-021961-03-02DR-110-GAMajor disasterFLOODSInland Flooding
1954-03-171954-03-17DR-16-GAMajor disasterTORNADOTornado
1953-05-021953-05-02DR-1-GAMajor disasterTORNADOTornado

FEMA recorded these with designated area Statewide and no county. Listed on every county page in the state; not counted with county rows.

Source

FEMA, OpenFEMA DisasterDeclarationsSummaries v2, version 2026-09-27T010817Z, pulled 2026-09-28, https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries (API)

Previous occurrences by hazard, with explicit no-event rows

HazardStorm Events recordsfull periodSince plan approvalrecordsDuring plan reviewrecordsLast 5 yearsrecordsDeclared incidentsdistinct incidentsDeclared since approvaldistinct incidentsPeriodStatement
Avalanche0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Coastal Flooding0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Cold Wave14000001996 to 2026-06-30Includes 1 Frost/Freeze record, event types the NRI definition of this hazard leaves out.
Drought42406101996 to 2026-06-30
Earthquake000000No Storm Events record; local data required (e.g., USGS).
Hail190036001955 to 2026-06-30
Heat Wave11000001996 to 2026-06-30
Hurricane17011301996 to 2026-06-30
Ice Storm7101101996 to 2026-06-30
Inland Flooding45004201996 to 2026-06-30
Landslide0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Lightning129001001996 to 2026-06-30
Strong Wind34801778001955 to 2026-06-30Includes 5 High Wind records and 16 Strong Wind records, event types the NRI definition of this hazard leaves out.
Tornado12000001950 to 2026-06-30
Tsunami0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Volcanic Activity0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Wildfire0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Winter Weather37125311996 to 2026-06-30

Sources

NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/

FEMA, OpenFEMA DisasterDeclarationsSummaries v2, version 2026-09-27T010817Z, pulled 2026-09-28, https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries (API)

NOAA National Weather Service, NWS county-public forecast zones correlation file, version bp03mr20 to bp16ap26 (11 files; newest bp16ap26), pulled 2026-09-28, https://www.weather.gov/gis/ZoneCounty

Notable Storm Events records

DateEvent typeMagnitude or extentDamagenominal dollarsDirect deaths, injuriesindirect not countedLocationFlagsWhy listed
2020-10-28Tropical Stormdamage not reported2, 0NWS zone GAZ034 (GWINNETT), zone-level: may include parts of neighboring countiesdeaths or injuries recorded
2018-06-01Thunderstorm Wind78 kt (90 mph) estimated gust$500,000 property; crops not reported (2018 dollars)0, 0LILBURN to SNELLVILLEB1-c worst recorded: Thunderstorm Wind
2017-09-11Tropical Storm$3,000,000 property; crops not reported, reported for the zone (2017 dollars)0, 0NWS zone GAZ034 (GWINNETT), zone-level: may include parts of neighboring countiesB1-c worst recorded: Hurricane, Tropical Storm, Tropical Depression
2009-09-21Flood$12,500,000 property; $0 crops (2009 dollars)0, 0BUFORD to CAROLINAB1-c worst recorded: Flash Flood, Flood, Lakeshore Flood
2009-04-13High Wind50 kt (58 mph) estimated gust$0 property; $0 crops, reported for the zone (2009 dollars)0, 1NWS zone GAZ034 (GWINNETT), zone-level: may include parts of neighboring countiesB1-c worst recorded: High Wind and Strong Wind (outside NRI Strong Wind definition)
2004-06-27Lightning$50,000 property; crops not reported (2004 dollars)3, 6SUGAR HILLdeaths or injuries recorded
2000-12-01Extreme Cold/Wind Chilldamage not reported0, 0NWS zone GAZ034 (GWINNETT), zone-level: may include parts of neighboring countiesB1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill
2000-01-22Ice Storm$980,000 property; crops not reported, reported for the zone (2000 dollars)0, 0NWS zone GAZ034 (GWINNETT), zone-level: may include parts of neighboring countiesB1-c worst recorded: Ice Storm
1999-07-20Heatdamage not reported0, 0NWS zone GAZ034 (GWINNETT), zone-level: may include parts of neighboring countiesB1-c worst recorded: Excessive Heat, Heat
1998-05-07Hail2.75 in$5,000 property; crops not reported (1998 dollars)0, 0DULUTH to DACULAB1-c worst recorded: Hail
1998-04-08TornadoF2, 15 mi within this county, 800 yd wide$50,000,000 property; crops not reported (1998 dollars)0, 10NORCROSS to LAWRENCEVILLEB1-c worst recorded: Tornado
1997-09-10Lightningdamage not reported1, 1LILBURNdeaths or injuries recorded

The full list is in the XLSX file, sheet "B1-d Storm Events history" (852 rows).

Storm Events records are more complete after 1996; before 1996 only Tornado (from 1950), Hail and Thunderstorm Wind (from 1955) exist. Zone-level records are placed with NWS zone-county files, which exist from 2020 on; an earlier record is placed by its zone number in the nearest later file only when its zone name matches that file, records from zones NWS renumbered are placed by name or left out, and a record whose zone is in no known file is left out of every count, so counts before 2020 can be low. Some current zones are also missing from the NWS files, so recent counts can be low too.

Sources

NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/

NOAA National Weather Service, NWS county-public forecast zones correlation file, version bp03mr20 to bp16ap26 (11 files; newest bp16ap26), pulled 2026-09-28, https://www.weather.gov/gis/ZoneCounty

FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-26T121003Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)

State-declared emergencies are not in federal data. Add them from your state emergency management agency.

Tribal and special-area declarations in this state are listed on the state page.

Supports B1-e: probability GEMA template B: Hazard profile (events and probability)

Probability: FEMA annualized frequency and descriptor per hazard

HazardFEMA annualized frequency (modeled)unit per rowUnitIn plain termsDescriptorDescriptor basisNRI events or days in its record period (hail, wind and tornado are area-weighted, so can be fractional)NRI periodLocationNote
Avalancheevents per year1994 to 2023 (30 years)see B1-fNot Applicable in NRI for this county; no descriptor.
Coastal Floodingevents per year at a location (modeled)not shownmodeledsee B1-fNot Applicable in NRI for this county; no descriptor.
Cold Wave0.842event-days per yearabout 0.842 days per yearLikelyevent-days in 6 of 30 years, 1996 to 2025 (20%)162005-11-12 to 2024-11-12 (19 years)countywideFrost/Freeze records are not counted in this descriptor: they record crop freezes, not cold waves.
Drought33.3event-days per yearabout 33.3 days per yearLikelyevent-days in 14 of 30 years, 1996 to 2025 (46.7%)1,1622000 to 2025 (25.25 years; D3 and D4 only)countywideNRI gives about 33.3 drought event-days a year here (its annualized frequency over 25.25 years; not its event count divided by the years), but Storm Events has a record in only 14 of 30 years. NRI counts from a different source that records far more events than Storm Events, so this descriptor reads much lower than NRI's frequency; read the two together.
Earthquake0.00196annual probability at a locationchance a given location in the county has at least minor-damage shaking in a year: 0.196%not shownmodeledsee B1-fDescriptor not assigned: the NRI value is the chance at a location in the county, not how often the hazard affects the county, and Storm Events does not record earthquakes.
Hail5.34events per yearabout 5.34 per yearHighly likelyFEMA annualized frequency (modeled)202.8 (modeled)1986 to 2023 (38 years)countywide
Heat Wave2.26event-days per yearabout 2.26 days per yearLikelyevent-days in 5 of 30 years, 1996 to 2025 (16.7%)412005-11-12 to 2024-11-12 (19 years)countywideNRI gives about 2.26 heat wave event-days a year here (its annualized frequency over 19 years; not its event count divided by the years), but Storm Events has a record in only 5 of 30 years. NRI counts from a different source that records far more events than Storm Events, so this descriptor reads much lower than NRI's frequency; read the two together.
Hurricane0.0321events per yearabout 1 in 31 yearsPossibleFEMA annualized frequency (modeled)81851 to 2024 (Atlantic)see B1-fNRI counts hurricane and tropical storm tracks passing within storm-force wind range; federal declarations are counted separately in B1-d and need not match.
Ice Storm1.16event-days per yearabout 1.16 days per yearLikelyevent-days in 5 of 30 years, 1996 to 2025 (16.7%)781946-12-31 to 2014-02-12 (67 years)countywideNRI gives about 1.16 ice storm event-days a year here (its annualized frequency over 67 years; not its event count divided by the years), but Storm Events has a record in only 5 of 30 years. NRI counts from a different source that records far more events than Storm Events, so this descriptor reads much lower than NRI's frequency; read the two together.
Inland Flooding1.18event-days per yearabout 1.18 days per yearLikelyevent-days in 16 of 30 years, 1996 to 2025 (53.3%)331996 to 2023 (28 years)see B1-f
Landslide0.392events per year (modeled)about 1 in 3 yearsLikelyFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Lightning59.7days per year with a strikeabout 59.7 days per yearHighly likelyFEMA annualized frequency (modeled)not shown1995 to 2023 (29 years; CONUS)countywide
Strong Wind2.54events per yearabout 2.54 per yearHighly likelyFEMA annualized frequency (modeled)971986 to 2023 (38 years)countywide
Tornado0.257events per yearabout 1 in 4 yearsLikelyFEMA annualized frequency (modeled)not shown1950 to 2023 (EF2+); 1986 to 2023 (EF0-1)see B1-f
Tsunamiannual probability at the most exposed location (used in place of a county value)not shownmodeledsee B1-fNot Applicable in NRI for this county; no descriptor.
Volcanic Activityannual probabilitynot shownmodeledsee B1-fNot Applicable in NRI for this county; no descriptor.
Wildfire0.000034annual probability at a locationchance a given location in the county burns in a year: 0.0034%Storm Events records in 0 of 30 years, 1996 to 2025 (0%)not shownmodeledsee B1-fNo Storm Events record of this hazard, 1996 to 2025; descriptor not assigned (the NRI value is the chance at a location in the county, not how often the hazard affects the county)
Winter Weather2.95event-days per yearabout 2.95 days per yearLikelyevent-days in 21 of 30 years, 1996 to 2025 (70%)562005-11-12 to 2024-11-12 (19 years)countywide

FEMA annualized frequency (modeled) comes from the National Risk Index v1.20 (December 2025). It is not recorded events divided by years, and what it measures depends on the hazard. For most hazards it estimates how often the hazard affects this county each year: it counts events or event-days (drought, heat wave, cold wave, winter weather, ice storm and inland flooding are in days per year; lightning is the number of days per year with a recorded cloud-to-ground strike, from the NOAA Storm Prediction Center daily lightning climatology); it may count events in the surrounding area (hail, strong wind, tornado, hurricane and ice storm use a 49 km grid and buffers) and is averaged over the county's area; and some hazards use a minimum value for places with no recorded event. Earthquake, wildfire and coastal flooding are different: FEMA computes them for each census block and averages them over the county, so the value is the chance (for coastal flooding, the modeled number of floods per year) at a location in the county, which is lower than the chance that the hazard strikes somewhere in the county. Earthquake is the chance of at least minor-damage shaking (U.S. Geological Survey model); wildfire is the chance that a location burns in a large fire (U.S. Forest Service burn probability); coastal flooding comes from FEMA flood zones and NOAA high-tide flooding, so it can be above 1 where high-tide flooding is frequent. Tsunami is the value at the county's most exposed location, from recorded events and modeled return periods. For these four hazards the packet gives no "1 in N years" and takes the descriptor from Storm Events (none for earthquake) unless the value is 1 or more a year. Landslide is a U.S. Geological Survey modeled county rate spread by slope susceptibility. Volcanic activity is the chance that a volcano affecting the county erupts in a year. Drought counts only extreme and exceptional drought (D3 and D4). Source: FEMA, National Risk Index Technical Documentation v1.20, sections 5.2.2 (Table 5), 5.2.3, 7.4, 10.4, 16.5, 17.1, 17.3.1, 17.5, 20.3.1, 21.4, 22.4 and 6 to 23.

Sources

FEMA, FEMA National Risk Index 1.20.0 (December 2025), county and census tract tables, version 1.20.0, pulled 2026-09-28, https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_Counties.zip (download, 25 MB), https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_CensusTracts.zip (download, 635 MB)

NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/

Descriptor scale used in this packet (defined per unit)

UnitDescriptorDefinition
events per yearHighly likely1 or more per year
events per yearLikelyabout once in 1 to 10 years
events per yearPossibleabout once in 10 to 100 years
events per yearUnlikelyless than once in 100 years
annual probabilityLikely10% to under 100% chance in a given year
annual probabilityPossible1% to under 10% chance in a given year
annual probabilityUnlikelyunder 1% chance in a given year
event-days (share of years)Highly likelyevent-days recorded in 90% or more of years
event-days (share of years)Likelyevent-days recorded in 10% to under 90% of years
event-days (share of years)Possibleevent-days recorded in some years but under 10% of years
lightning strike-daysHighly likelycloud-to-ground strikes on 1 or more days per year

Sources

FEMA, FEMA National Risk Index 1.20.0 (December 2025), county and census tract tables, version 1.20.0, pulled 2026-09-28, https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_Counties.zip (download, 25 MB), https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_CensusTracts.zip (download, 635 MB)

NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/

Intensity bands: historical frequency (Storm Events)

HazardBandYearsEventscounty-coded recordsYears in periodEvents per yearevents / years
Hail1.00-1.99 in1996 to 202588302.93
Hail2.00 in+1996 to 20255300.167
Strong Wind (Thunderstorm Wind records)50-64 kt1996 to 2025178305.93
Strong Wind (Thunderstorm Wind records)65 kt+1996 to 20251300.0333
Strong Wind (Thunderstorm Wind records)unmeasured or below 50 kt1996 to 202586302.87
TornadoEF0-11996 to 20252300.0667
TornadoEF2-31996 to 20252300.0667
TornadoEF4-51996 to 20250300
Tornadounrated (EFU)1996 to 20250300

Hail smaller than 1 inch is not counted: on 2010-01-05 the National Weather Service raised its severe-hail threshold from 3/4 inch to 1 inch, so smaller reports became less common after 2009 (NWS Service Change Notice 09-52). NRI hail frequency uses a 0.75 inch threshold.

Source

NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/

Optional: future conditions. Not a required item in the 2025 FEMA Local Mitigation Planning Policy Guide; some states ask for it. The federal Climate Mapping for Resilience and Adaptation (CMRA) site gives county exposure to future climate conditions.

Supports B1-f: variation across the planning area GEMA template F: Multi-jurisdictional differences

Range of census tract risk within the county

HazardTractsrated of allRisk score minNRI score, 0 to 100MedianMaxTracts by ratingNote
Avalanche0 of 220Not Applicable 220
Coastal Flooding0 of 220Not Applicable 220
Cold Wave220 of 22030.847.165.6Relatively Moderate 110, Relatively Low 110National data give a county-wide or coarse (49 km grid or NWS zone) frequency for this hazard, so they cannot show members' hazard differing. The tract range above mostly reflects where buildings and people are. Confirm locally.
Drought1 of 22097.397.397.3Relatively Moderate 1, No Rating 219National data give a county-wide or coarse (49 km grid or NWS zone) frequency for this hazard, so they cannot show members' hazard differing. Agriculture is all of NRI's expected annual loss for this hazard in the county, so the tract range above mostly reflects where crop and livestock value is, not where buildings and people are. Confirm locally.
Earthquake220 of 22020.652.885.6Relatively Moderate 6, Relatively Low 169, Very Low 45
Hail220 of 22052.473.696.1Relatively High 2, Relatively Moderate 155, Relatively Low 63National data give a county-wide or coarse (49 km grid or NWS zone) frequency for this hazard, so they cannot show members' hazard differing. The tract range above mostly reflects where buildings and people are. Confirm locally.
Heat Wave220 of 22011.028.952.8Relatively Low 206, Very Low 14National data give a county-wide or coarse (49 km grid or NWS zone) frequency for this hazard, so they cannot show members' hazard differing. The tract range above mostly reflects where buildings and people are. Confirm locally.
Hurricane220 of 22030.242.560.1Relatively Low 3, Very Low 217
Ice Storm220 of 22024.861.294.3Relatively High 1, Relatively Moderate 57, Relatively Low 158, Very Low 4National data give a county-wide or coarse (49 km grid or NWS zone) frequency for this hazard, so they cannot show members' hazard differing. The tract range above mostly reflects where buildings and people are. Confirm locally.
Inland Flooding220 of 2203.947.393.4Relatively High 23, Relatively Moderate 85, Relatively Low 91, Very Low 21
Landslide220 of 22019.463.595.5Relatively Low 25, Very Low 195
Lightning220 of 22040.165.392.0Relatively High 28, Relatively Moderate 179, Relatively Low 13National data give a county-wide or coarse (49 km grid or NWS zone) frequency for this hazard, so they cannot show members' hazard differing. The tract range above mostly reflects where buildings and people are. Confirm locally.
Strong Wind220 of 22023.440.772.4Relatively Moderate 12, Relatively Low 208National data give a county-wide or coarse (49 km grid or NWS zone) frequency for this hazard, so they cannot show members' hazard differing. The tract range above mostly reflects where buildings and people are. Confirm locally.
Tornado220 of 22037.857.395.8Very High 1, Relatively High 9, Relatively Moderate 144, Relatively Low 66
Tsunami0 of 220Not Applicable 220
Volcanic Activity0 of 220Not Applicable 220
Wildfire219 of 22020.341.278.3Relatively Low 2, Very Low 217, No Rating 1
Winter Weather220 of 22019.226.357.2Relatively Moderate 1, Relatively Low 219National data give a county-wide or coarse (49 km grid or NWS zone) frequency for this hazard, so they cannot show members' hazard differing. The tract range above mostly reflects where buildings and people are. Confirm locally.

Rated tracts only: No Rating (score 0.0), Not Applicable and Insufficient Data tracts are counted but not used for the minimum, median and maximum.

Source

FEMA, FEMA National Risk Index 1.20.0 (December 2025), county and census tract tables, version 1.20.0, pulled 2026-09-28, https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_Counties.zip (download, 25 MB), https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_CensusTracts.zip (download, 635 MB)

Per-member block (Starter, confirm locally)

MemberTypePlan statusRepetitive lossFMA RL and SRL (44 CFR 77.2); repeat-flood, any definitionPublic Assistance matchedfederal share obligated, nominal dollarsEvent records naming this placeall years; since the member's planNotes
Gwinnett County (unincorporated area)UnincorporatedApproved, expires 2030-08-07FMA RL 2, SRL 4; any 23$9,335,950.180; 0Includes $261,684.38 for declarations not counted as hazard incidents (DR-4501-GA, EM-3218-GA).
Auburn cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 0none found0; 0
Berkeley Lake cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 0$3,703,085.6215; 0
Braselton townTownApproved, expires 2031-07-23FMA RL 0, SRL 0; any 0none found0; not yet coveredAlso approved under plan 108611 (Hall County, expires 2028-03-07); plan 111013 (Gwinnett County, expires 2030-08-07). FEMA's plan status map shows one plan per jurisdiction and may show one of these; this packet uses the approved plan that expires last.
Buford cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 1$115,808.6746; 0Also approved under plan 108611 (Hall County, expires 2028-03-07). FEMA's plan status map shows one plan per jurisdiction and may show one of these; this packet uses the approved plan that expires last.
Dacula cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 0$3,076.2048; 0
Duluth cityCityApproved, expires 2030-08-07FMA RL 0, SRL 1; any 8$147,849.8668; 0
Grayson cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 0none found30; 0
Lawrenceville cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 1$420,755.4582; 0Includes $9,748.76 for declarations not counted as hazard incidents (EM-3218-GA).
Lilburn cityCityApproved, expires 2030-08-07FMA RL 0, SRL 1; any 2$99,666.5762; 0
Loganville cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 0none found0; 0
Norcross cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 0$394,539.1272; 0Includes $157,621.21 for declarations not counted as hazard incidents (DR-4501-GA).
Peachtree Corners cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 0$33,259.680; 0
Snellville cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 0$25,835.9548; 0
Sugar Hill cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 0$66,256.4821; 0
Suwanee cityCityApproved, expires 2030-08-07FMA RL 0, SRL 0; any 0$63,630.9440; 0

Member rows are whole NFIP communities and need not add up to the county total: a community that extends into another county is counted in full on each member row, while the county table counts only its part in this county.

School districts and special districts get a plan clock row only.

Sources

FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-26T121003Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)

FEMA, OpenFEMA NfipMultipleLossProperties v1, version 2026-08-04T164045Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/NfipMultipleLossProperties (API)

FEMA, OpenFEMA PublicAssistanceFundedProjectsSummaries v1, version 2026-09-26T151157Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/PublicAssistanceFundedProjectsSummaries (API)

NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/

Supports B2-a and B2-b: assets and impacts GEMA template C/D: Community exposure; Estimate of potential losses

Local data required

County-level starter. The plan must describe impacts for each participant and its own assets.

  • Critical facilities and lifelines per hazard
  • A problem statement per participant per hazard
  • Changes in development in hazard-prone areas since the last approval, or a statement of none (E1-a)
  • Future assets

County-level starter: exposure, expected annual loss and damage since the plan

HazardBuilding exposuremodeled dollarsAgriculture exposuremodeled dollarsPopulation exposedpeopleEAL buildingsmodeled dollars per yearEAL agriculturemodeled dollars per yearEAL population equivalencestatistical value of life and injury, $13.7M per life, not property damageEAL as % of exposurebuildings; agriculture where notedStorm Events damage since 2025-08-08county-coded records, property plus crops, nominal dollarsZone-level damage since planproperty plus crops, reported for the zonePublic Assistance since plannominal dollars; see noteNote
AvalancheNot Applicable in NRI for this county
Coastal FloodingNot Applicable in NRI for this county
Cold Wave$196,961,963,421$21,664,701956,460$116,183$16,300$10,792,918under 0.0001%
Drought$19,858,060$249,0361.25% (agriculture)$0NRI has no building exposure for this hazard; agriculture shown
Earthquake$332,973,933,690957,062$8,454,879$2,010,3670.00254%
Hail$196,961,993,393$21,664,701956,460$6,689,033$49$175,9220.0034%
Heat Wave$196,961,963,421$21,664,701956,460$301$40$4,868,268under 0.0001%
Hurricane$194,692,356,068$21,657,405944,085$730,589$7,372$39,1710.000375%
Ice Storm$196,961,882,853956,459$1,865,346$14,8290.000947%
Inland Flooding$196,853,035,326$860,93010,116$144,327,787$6,417$528,292n/a (see note)NRI counts the full building value of any census block with some flood loss; this is not the value of buildings in the floodplain. Use local FIRM overlays for B2-a/B2-b. EAL as % of exposure: n/a.
Landslide$8,057,286,54239,730$15,953$5430.000198%
Lightning$196,961,993,393956,460$869,489$3,534,2380.000441%
Strong Wind$196,961,993,393$21,664,701956,460$725,386$44$2,067,6850.000368%
Tornado$196,961,993,393$21,664,701956,460$16,233,991$616$6,949,7280.00824%
TsunamiNot Applicable in NRI for this county
Volcanic ActivityNot Applicable in NRI for this county
Wildfire$22,877,157,964$3,088,805137,528$35,011$2$7,2100.000153%
Winter Weather$196,961,963,421$21,664,701956,460$111,330$30$42,248under 0.0001%none found (1 declaration)

Totals since 2025-08-08 (Storm Events through 2026-06-30): 0 county-coded records, 0 with a damage value recorded (including $0), $0; 6 zone-level records, 4 with a damage value recorded (including $0), $0 reported for the zone; Public Assistance on counted declarations none found (1 declaration, 0 with PA).

Total = buildings + agriculture + population equivalence; FEMA values each expected death (or 10 injuries) at $13.7 million (2024 dollars).

FEMA does not split Public Assistance by hazard. A declaration mapped to several hazards is listed under each of them with its full amount, so the per-hazard column must not be added up; the unit total counts each declaration once.

Dollars are nominal (as reported), labeled with the year; not adjusted for inflation.

Sources

FEMA, FEMA National Risk Index 1.20.0 (December 2025), county and census tract tables, version 1.20.0, pulled 2026-09-28, https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_Counties.zip (download, 25 MB), https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_CensusTracts.zip (download, 635 MB)

NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/

NOAA National Weather Service, NWS county-public forecast zones correlation file, version bp03mr20 to bp16ap26 (11 files; newest bp16ap26), pulled 2026-09-28, https://www.weather.gov/gis/ZoneCounty

FEMA, OpenFEMA DisasterDeclarationsSummaries v2, version 2026-09-27T010817Z, pulled 2026-09-28, https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries (API)

FEMA, OpenFEMA PublicAssistanceFundedProjectsSummaries v1, version 2026-09-26T151157Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/PublicAssistanceFundedProjectsSummaries (API)

FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-26T121003Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)

The 2024 Georgia Hazard Mitigation Strategy says the State provides a Level 2 Hazus analysis as part of each county's plan update, and GMIS holds critical-facility data. Use them for B2-a and B2-b. https://gema.georgia.gov/document/document/georgia-hazard-mitigation-strategy-2024/download

The 2024 Georgia Hazard Mitigation Strategy notes that FEMA restricted access to repetitive-loss property data, so GMIS repetitive-loss reports may not be available; ask GEMA/HS or the state NFIP coordinator for the current list. https://gema.georgia.gov/document/document/georgia-hazard-mitigation-strategy-2024/download

Rows are also labeled with the GEMA template per-hazard section letter (A to I). https://gema.georgia.gov/document/publication/local-hazard-mitigation-plan-update-template/download

Supports B2-a: context GEMA template I: Social vulnerability

County context

MeasureValue
Population956,460
Building value (total, not at risk)$196,961,993,393
Agriculture value (total, not at risk)$21,664,701
NRI risk rating (all hazards)Relatively High
Expected annual loss, buildings and agriculture, all hazards$180,455,185
Expected annual loss, population equivalence, all hazards (NRI values each statistical life at $13.7M; a modeled value of expected deaths and injuries, not property damage)$31,031,419
Social vulnerability ratingRelatively Low
Community resilience ratingVery Low
NRI versionDecember 2025

FEMA's all-hazard expected annual loss total adds buildings, agriculture and population equivalence; the two parts are shown separately so the property figure is not read as including the statistical value of life.

Source

FEMA, FEMA National Risk Index 1.20.0 (December 2025), county and census tract tables, version 1.20.0, pulled 2026-09-28, https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_Counties.zip (download, 25 MB), https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_CensusTracts.zip (download, 635 MB)

Supports B2-c: repetitive loss

Repetitive loss in this county, both definitions

DefinitionPropertiesSevere repetitive lossProperties
Repetitive loss, FMA definition (44 CFR 77.2)2Severe repetitive loss, FMA definition (44 CFR 77.2)6
Repetitive loss, NFIP insurance definition31Severe repetitive loss, NFIP insurance definition3

Your state NFIP coordinator's list may use the NFIP insurance definition, so its counts can be higher.

Repeat-flood properties: county and state-level rows

ScopeRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
County total2631335013
DULUTH, CITY OF0181805
LAWRENCEVILLE, CITY OF0010101
LILBURN, CITY OF0121200
GWINNETT COUNTY *241912306
BUFORD, CITY OF0010101
State level, not in this county: county not reported2252616

Repeat-flood properties by plan member (NFIP community)

MemberNFIP community IDRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredpropertiesNote
Gwinnett County (unincorporated area)130322241912306
Auburn city1304980000000
Berkeley Lake city1304500000000
Braselton town1303430000000
Buford city1303230010101
Dacula city1303240000000
Duluth city1300980181805
Grayson city1303250000000
Lawrenceville city1300990010101
Lilburn city1301000121200
Loganville city1303260000000
Norcross city1301010000000
Peachtree Corners city1351760000000
Snellville city1301020000000
Sugar Hill city1304740000000
Suwanee city1303280000000

Per-member types: XLSX sheet 'B2-c Members'.

Member rows are whole NFIP communities and need not add up to the county total: a community that extends into another county is counted in full on each member row, while the county table counts only its part in this county.

County repeat-flood properties by occupancy group

Occupancy groupRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
single-family residential2626330010
2 to 4 unit residential0000000
other residential0010100
non-residential0040403
not reported0000000

Institutional properties cannot be separated in this data: FEMA's occupancy groups have no institutional class, so they fall in non-residential or other residential in the table by occupancy group.

FMA RL and FMA SRL are the Flood Mitigation Assistance definitions (44 CFR 77.2), the ones the FEMA Local Mitigation Planning Policy Guide cites; OpenFEMA's fmaRl field description omits the Increased Cost of Compliance clause of 44 CFR 77.2(i). NFIP repetitive loss (FEMA insurance definition, nfipRl) is 2 or more claims over $1,000 in 10 years and can drop to false when a property is mitigated. Also shown: NFIP severe repetitive loss, any category, mitigated and currently insured.

Your state NFIP coordinator's list may use the NFIP insurance definition, so its counts can be higher.

Counts are aggregates of FEMA's public NFIP Multiple Loss Properties file (as of 2026-08-02). No property is identified. County assignment is FEMA's geocode.

Counts may differ from your state NFIP coordinator's list, which is the source the Handbook names.

In this county 1 property is FMA repetitive loss but not NFIP repetitive loss, and 30 properties are NFIP repetitive loss but not FMA repetitive loss.

Exact counts; no count suppression.

Sources

Every table above lists its own sources. The full list, for the plan's bibliography (FEMA review item A4-a):

  1. FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-26T121003Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)
  2. FEMA, OpenFEMA DisasterDeclarationsSummaries v2, version 2026-09-27T010817Z, pulled 2026-09-28, https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries (API)
  3. FEMA, OpenFEMA PublicAssistanceFundedProjectsSummaries v1, version 2026-09-26T151157Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/PublicAssistanceFundedProjectsSummaries (API)
  4. FEMA, OpenFEMA NfipMultipleLossProperties v1, version 2026-08-04T164045Z, pulled 2026-09-28, https://www.fema.gov/api/open/v1/NfipMultipleLossProperties (API)
  5. FEMA, FEMA National Risk Index 1.20.0 (December 2025), county and census tract tables, version 1.20.0, pulled 2026-09-28, https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_Counties.zip (download, 25 MB), https://www.fema.gov/about/reports-and-data/openfema/nri/v120/NRI_Table_CensusTracts.zip (download, 635 MB)
  6. NOAA NCEI, NOAA NCEI Storm Events Database, details files (csvfiles v1.0), version c20260918, pulled 2026-09-28, https://www.ncei.noaa.gov/pub/data/swdi/stormevents/csvfiles/
  7. NOAA National Weather Service, NWS county-public forecast zones correlation file, version bp03mr20 to bp16ap26 (11 files; newest bp16ap26), pulled 2026-09-28, https://www.weather.gov/gis/ZoneCounty
  8. U.S. Census Bureau, Census 2024 Gazetteer, 2020 place by county, CT county-to-cousub crosswalk, version 2024-gazetteer, pulled 2026-09-28, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_counties_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_cousubs_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_place_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_unsd_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_elsd_national.zip, https://www2.census.gov/geo/docs/maps-data/data/gazetteer/2024_Gazetteer/2024_Gaz_scsd_national.zip, https://www2.census.gov/geo/docs/reference/codes2020/national_place_by_county2020.txt, https://www2.census.gov/geo/docs/reference/ct_change/ct_cou_to_cousub_crosswalk.xlsx

GEMA template per-hazard letters (A to I) next to the FEMA item. No letter is documented for repetitive loss; place B2-c per your GEMA template.

OpenFEMA disclaimer

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

Hazard Plain is an independent product built from public federal data, not a FEMA document, and not reviewed or endorsed by FEMA or GEMA/HS; GEMA template letters are a cross-reference only.

Reuse, citation and corrections

Reuse and citation: Hazard Plain text and tables are licensed under Creative Commons Attribution 4.0 International (CC BY 4.0, https://creativecommons.org/licenses/by/4.0/); credit Hazard Plain and the release. The underlying federal data are public domain; OpenFEMA data are also subject to the OpenFEMA terms and conditions.

Cite this: Hazard Plain (2026). Gwinnett County, GA: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-28; County area 13135). Preview: automated baseline. Built from FEMA OpenFEMA, the FEMA National Risk Index and NOAA NCEI Storm Events; source versions in the packet's Sources list.

Corrections: to report an error, name the packet, the table and what your records show. Contact: to be added

Hazard Plain release 2026-10. As of 2026-09-28; Storm Events data through 2026-06-30. File hazard-plain_2026-10_GA_13135. Preview: automated baseline.