Hazard Plain Automated baseline

Alpine County, CA

Risk-assessment baseline packet

County FIPS:
06003
Release:
2026-10
Data as of:
2026-09-30
Storm Events data through:
2026-06-30

Hazard Plain is an independent product built from public federal data. It is not a FEMA document and is not reviewed or endorsed by FEMA or any state agency.

Hazard Plain release 2026-10, as of 2026-09-30.

Summary

Plan status as of 2026-09-30: Expired on 2023-08-16. Plan: Alpine County (FEMA plan 102700), approved 2018-08-17.

Since the plan was approved on 2018-08-17: 4 new hazard declarations (3 incidents) and 490 NOAA Storm Events records; details under "What changed since your last plan".

Highest expected annual loss (FEMA National Risk Index, modeled total; see B1-a): Avalanche ($1,825,637 a year), Inland Flooding ($1,392,587) and Wildfire ($1,155,737).

The tables that follow are organized by the items of FEMA's Local Mitigation Plan Review Tool, Element B (B1-a to B2-c); each heading says which item its tables support.

Plan clock

Status:
Expired on 2023-08-16
Plan:
Alpine County (FEMA plan 102700)
Approved:
2018-08-17
Days since expiry:
1,141
Update underway:
none recorded in FEMA's plan tracker

Until a new plan is approved, FEMA mitigation project grants (HMGP, FMA) need a FEMA exception (44 CFR 201.6(a)(3)).

What changed since your last plan (approved 2018-08-17)

New federal declarations:
4 new hazard declarations (3 incidents): EM-3571-CA (Caldor Fire), DR-4683-CA (Severe Winter Storms, Flooding, Landslides, and Mudslides), EM-3592-CA (Severe Winter Storms, Flooding, Landslides, and Mudslides), DR-4699-CA (Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, and Mudslides); also 2 COVID-19 declarations (not counted)
Storm Events records since approval:
490 records (data through 2026-06-30)
Repetitive loss now:
FMA RL 0, SRL 0 (44 CFR 77.2); any definition: 0
Repeat-flood change:
this release sets the baseline count.

Sources: 1, 2, 4, 6 (numbered list at the end)

Plan status for every jurisdiction listed in this county

Source: 1

JurisdictionTypeStatusPlanApprovedExpiresDays to expirynegative = days since expiry
Alpine CountyCountyExpired on 2023-08-16Alpine County (FEMA plan 102700)2018-08-172023-08-16-1,141
Name not given in FEMA data (ID R09_202706)School/School DistrictExpired on 2023-08-16Alpine County (FEMA plan 102700)2018-08-172023-08-16-1,141
Bear Valley Water DistrictWater/Sewer AuthorityExpired on 2023-08-16Alpine County (FEMA plan 102700)2018-08-172023-08-16-1,141
Kirkwood Meadows Public Utilities DistrictElectric/Power AuthorityExpired on 2023-08-16Alpine County (FEMA plan 102700)2018-08-172023-08-16-1,141
Markleeville Public Utilities DistrictElectric/Power AuthorityExpired on 2023-08-16Alpine County (FEMA plan 102700)2018-08-172023-08-16-1,141

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

Supports FEMA checklist item B1-a: hazard identification

Hazards NRI does not cover (local data needed)

  • 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)

Sources: 5, 6

Rank by EALHazardNRI risk ratingEAL ratingEAL buildingsmodeled dollars per yearEAL agriculturemodeled dollars per yearCost of expected deaths and injuriesFEMA's dollar value per year, not property damageEAL total (see note)modeled dollars per yearStorm Events records, 1996 to 2026-06-30countWhy this hazard can be left outNRI Not Applicable, no declaration and no Storm Events record since 1996Storm Events coverage note
1AvalancheRelatively HighRelatively Moderate$36n/a$1,825,600$1,825,63720
2Inland FloodingVery LowVery Low$1,392,459under $1$128$1,392,5874
3WildfireRelatively ModerateRelatively Moderate$1,129,823$76$25,838$1,155,73725
4EarthquakeVery LowRelatively Low$300,903n/a$8,328$309,231Storm Events does not record earthquakes.
5Winter WeatherRelatively LowRelatively Low$6,741under $1$54,692$61,432948
6Strong WindVery LowVery Low$4,962$149$14,922$20,034199Includes 186 High Wind and 12 Strong Wind records (NOAA non-thunderstorm wind types, outside NRI's Strong Wind definition).
7LightningVery LowVery Low$859n/a$9,192$10,0520No recorded events in Storm Events since 1996 (data through 2026-06-30).
8Heat WaveVery LowVery Low$5$34$4,786$4,8266
9LandslideRelatively LowVery Low$475n/a$3,636$4,11114
10HailVery LowVery Low$230$259$975$1,4645
11TornadoVery LowVery Low$181$2$13$1970No recorded events in Storm Events since 1996 (data through 2026-06-30).
12Volcanic ActivityVery LowVery Lowunder $1n/aunder $1under $10No recorded events in Storm Events since 1996 (data through 2026-06-30).
13Cold WaveNo RatingNo Expected Annual Losses$0$0$0$05
14DroughtNo RatingNo Expected Annual Lossesn/a$0n/a$031
HurricaneNot ApplicableNot Applicable0NRI rates hurricane Not Applicable for this county, and no counted federal declaration for this county names it (EM-3248-CA names it but is not counted as a local occurrence; see B1-d).No recorded events in Storm Events since 1996 (data through 2026-06-30).
Ice StormNot ApplicableNot Applicable0Declared 1 time; no Storm Events record of this type.

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

NRI risk rating combines expected annual loss with social vulnerability and community resilience; EAL rating rates expected annual loss alone. Both compare this county with all U.S. counties.

Local data needed: state and local lightning and volcanic activity records (Storm Events records these hazards only in part).

Not applicable to this county per NRI, with no federal declaration and no Storm Events record since 1996: coastal flooding and tsunami. That is the evidence for leaving them out of the plan.

The state hazard mitigation plan also lists hazards for this county; FEMA asks the plan to explain any hazard it leaves out.

Supports FEMA checklist item B1-b: hazard location

Affects the whole county (national data give no location within it): Cold Wave, Drought, Hail, Heat Wave, Ice Storm, Lightning, Strong Wind and Winter Weather.

Inland Flooding: The 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.

NRI rating of the county's single census tract

Source: 5

HazardCensus tractNRI risk rating, score 0 to 100
Avalanchetract 100 (Relatively Moderate, 88.1)
Earthquaketract 100 (Relatively Moderate, 84.0)
Hurricaneno tract has a National Risk Index rating for this hazard
Landslidetract 100 (Relatively Moderate, 96.5)
Tornadotract 100 (Very Low, 1.6)
Volcanic Activitytract 100 (Very Low, 41.2)
Wildfiretract 100 (Very High, 99.2)

A tract number is the Census tract number (for example 100 is Census Tract 100). FEMA's Resilience Analysis and Planning Tool maps the National Risk Index for every tract: https://www.fema.gov/emergency-managers/practitioners/resilience-analysis-and-planning-tool

Supports FEMA checklist item B1-c: hazard extent

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

Sources: 6, 7

HazardScaleRecordscount and yearsObserved rangeWorst recorded eventMost damaging (when different)How it applies to jurisdictionsNote
Avalanchenone (count and damage only)20 records, 1996 to 2026 (20 zone-level)No damage reported in 20 records.Countywide (zone-level records).
Cold/Wind Chill, Extreme Cold/Wind Chillwind chill5 records, 1997 to 2025 (5 zone-level)3 days; 1 with a recorded value3 consecutive days, 1997-01-13 to 1997-01-15, zone-levelCountywide (zone-level records).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's Cold Wave definition)crop damage0
DroughtU.S. Drought Monitor scale (D0 to D4)31 records, 2015 to 2023 (31 zone-level)61 days to 460 days (median 123 days); 5 with a recorded value460 days (about 15.1 months), 2021-10-08 to 2023-01-10, a run of 16 consecutive Storm Events drought records, zone-levelCountywide (zone-level records).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)0Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hailhail size (inches)5 records, 1998 to 20200.75 in to 1.75 in (median 1 in); 5 with a recorded value1.75 in hail, 2015-07-20; same size also recorded on 2015-07-20No event record names a jurisdiction in the plan.
Excessive Heat, Heatheat index (in event narratives)6 records, 2021 to 2023 (6 zone-level)2 days to 6 days (median 3.5 days); 6 with a recorded value6 consecutive days, 2022-09-04 to 2022-09-09, zone-levelCountywide (zone-level records).
Hurricane, Tropical Storm, Tropical DepressionSaffir-Simpson0Storm Events files every zone of a storm's episode under the storm's type; flooding from the storm is filed as Flood or Flash Flood records.
Ice StormSperry-Piltz ice scale (local data)0
Flash Flood, Flood, Lakeshore Flooddamage and flood days (flood depth: FIRM)4 records, 1997 to 2021 (2 zone-level)Flood, 2005-12-31, $1,000,000 property; crops not reported (2005 dollars)No event record names a jurisdiction in the plan. Zone-level records (2) apply countywide.Flood depth: see the FEMA Flood Insurance Rate Map. Storm Events damage is often $0 or blank for floods, major ones included; FEMA Public Assistance by declaration (B1-d) shows which floods cost the most.
Debris Flownone (count and damage only)14 records, 1998 to 2025 (4 zone-level)Debris Flow, 2005-12-22, $2,000 property; crops not reported (2005 dollars); NWS zone CAZ072No event record names a jurisdiction in the plan. Zone-level records (4) apply countywide.
Lightningannualized frequency (the measure FEMA's Local Mitigation Planning Handbook names)0Storm Events lists lightning with damage or casualties.
High Wind and Strong Wind (outside NRI's Strong Wind definition)wind speed (kt and mph)198 records, 1996 to 2026 (198 zone-level)22 kt (25 mph) to 173 kt (199 mph) (median 69 kt (79 mph)); 197 with a recorded value173 kt (199 mph) measured gust, High Wind, 2017-02-20; NWS zone CAZ069High Wind, 2014-12-30, $800,000 property; $0 crops (zone total, 2014 dollars)Countywide (zone-level records).
Thunderstorm Windwind speed (kt and mph)1 record, 2000No wind speed recorded in 1 record.No event record names a jurisdiction in the plan.
TornadoEnhanced Fujita (Fujita before Feb 2007)0Before 1996 a tornado is listed once, under the county where it began, with its whole path's rating and length; from 1996 on, each county lists its own segment. Length is not used to rank tornadoes (see Methods).
Volcanic Ash, Volcanic AshfallVolcanic Explosivity Index (local data)0
Wildfireacres burned (local data)25 records, 2007 to 2024 (25 zone-level)Wildfire, 2007-06-24, $500,000,000 property; crops not reported (2007 dollars), 3 direct injuries (reported for the zone); NWS zone CAZ072Countywide (zone-level records).
Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleetnone in data (snowfall: local data)948 records, 1996 to 2026 (948 zone-level)Heavy Snow, 2002-04-15, $500,000 property; crops not reported (2002 dollars), 4 direct injuries (reported for the zone); NWS zone CAZ072Countywide (zone-level records).

In event narratives only (local data needed): wind chill, temperature, heat index, ice thickness, acres burned and snow depth; any physical measure of avalanche, debris flow, lightning and volcanic ash, volcanic ashfall.

Storm Events records are more complete after 1996; before 1996 only Tornado (from 1950), Hail and Thunderstorm Wind (from 1955) exist. Zone-level records from zones that no NWS zone-county file places in this county (mostly before 2020) are not counted here (the Methods page explains the zone matching).

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

Supports FEMA checklist item B1-d: previous occurrences

Federal declarations for this county: 15 declarations covering 11 separate hazard incidents counted in this packet (declarations for the same incident count once; non-natural and evacuation-only declarations are not counted).

Federal disaster declarations for this county

Sources: 1, 2, 3

DeclaredIncident beganFEMA numberTypeTitleMapped hazardCounty Public Assistancefederal share obligated, nominal dollarsFlagsNotes
2023-04-032023-02-21DR-4699-CAMajor disasterSevere Winter Storms, Straight-Line Winds, Flooding, Landslides, and MudslidesIce Storm; Inland Flooding; Landslide; Strong Wind; Winter Weather$71,887.38new since last plan; within last 5 years
2023-03-102023-03-09EM-3592-CAEmergencySevere Winter Storms, Flooding, Landslides, and MudslidesInland Flooding (primary); also designated: Landslide, Winter Weatherno Public Assistance recordednew since last plan; within last 5 yearssame incident as DR-4699
2023-01-142022-12-27DR-4683-CAMajor disasterSevere Winter Storms, Flooding, Landslides, and MudslidesInland Flooding (primary); also designated: Landslide, Winter Weather$659,571.94new since last plan; within last 5 years
2021-09-012021-08-14EM-3571-CAEmergencyCaldor FireWildfireno Public Assistance recordednew since last plan
2020-03-222020-01-20DR-4482-CAMajor disasterCOVID-19 PandemicNon-natural, not countedno Public Assistance recordednew since last plan
2020-03-132020-01-20EM-3428-CAEmergencyCOVID-19Non-natural, not countedno Public Assistance recordednew since last plansame incident as DR-4482
2017-04-012017-02-01DR-4308-CAMajor disasterSevere Winter Storms, Flooding, and MudslidesInland Flooding (primary); also designated: Landslide, Winter Weather$204,237.43
2006-02-032005-12-17DR-1628-CAMajor disasterSevere Storms, Flooding, Mudslides, and LandslidesInland Flooding; Landslide$247,691.05
2005-09-132005-08-29EM-3248-CAEmergencyHurricane Katrina EvacuationHurricane: evacuation support, not a local hazard event; not countedno Public Assistance recorded
1997-01-041996-12-28DR-1155-CAMajor disasterSevere Storms, Flooding, Mud and LandslidesInland Flooding; Landslideno Public Assistance recorded
1995-03-121995-02-13DR-1046-CAMajor disasterSevere Winter Storms, Flooding Landslides, Mud FlowInland Flooding; Landslide; Winter Weatherno Public Assistance recorded
1993-02-031993-01-05DR-979-CAMajor disasterSevere Winter Storm, Mud & Land Slides, & FloodingInland Flooding (primary); also designated: Landslide, Winter Weatherno Public Assistance recorded
1986-02-211986-02-12DR-758-CAMajor disasterSevere Storms & FloodingInland Floodingno Public Assistance recorded
1977-01-201977-01-20EM-3023-CAEmergencyDroughtDroughtno Public Assistance recorded
1964-12-241964-12-24DR-183-CAMajor disasterHeavy Rains & FloodingInland Floodingno Public Assistance recorded

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.

Statewide declarations

Source: 2

DeclaredIncident beganFEMA numberTypeTitleMapped hazard
1964-04-011964-04-01DR-169-CAMajor disasterSeismic Sea WaveTsunami
1963-12-211963-12-21DR-161-CAMajor disasterFlood Due to Broken DamOther, not an NRI hazard; not counted
1963-02-251963-02-25DR-145-CAMajor disasterSevere Storms, Heavy Rains & FloodingInland Flooding
1962-10-241962-10-24DR-138-CAMajor disasterSevere Storms & FloodingInland Flooding
1962-03-061962-03-06DR-122-CAMajor disasterFloodsInland Flooding
1961-11-161961-11-16DR-119-CAMajor disasterFire (Los Angeles County)Wildfire
1958-04-041958-04-04DR-82-CAMajor disasterHeavy Rainstorms & FloodInland Flooding
1956-12-291956-12-29DR-65-CAMajor disasterForest FireWildfire
1955-12-231955-12-23DR-47-CAMajor disasterFloodInland Flooding
1954-02-051954-02-05DR-15-CAMajor disasterFlood & ErosionInland Flooding

FEMA recorded these with designated area Statewide and no county, so they are listed on every county page in the state and not counted with county rows. Local data needed: whether each one affected this county.

5 Fire Management declarations (1977-08-07 to 1988-09-13) FEMA filed as Statewide with no county; each names one local fire. Listed on the state page.

Public Assistance filed under this county for declarations that do not list it: 1 row, $241,189

Sources: 2, 3

FEMA numberDeclaredTitleApplicantPA obligatedfederal share obligated, nominal dollars
DR-4301-CA2017-02-14Severe Winter Storms, Flooding, and MudslidesKIRKWOOD MEADOWS PUBLIC UTILITY DISTRICT$241,189

FEMA's Public Assistance summaries file these applicants under this county, but FEMA's declaration rows for these disasters do not designate it (an electric cooperative or district serving several counties, for example). Not in any declaration row above and not counted.

Previous occurrences by hazard, with explicit no-event rows

Sources: 2, 6, 7

HazardStorm Events records, all years on file(years in the Period column)Since plan approvalrecordsIn the 12 months before plan approvalrecordsLast 5 yearsrecordsDeclared incidents, all yearsseparate disastersDeclared since approvalseparate disastersPeriodStatement
Avalanche20523001996 to 2026-06-30
Cold Wave5402001996 to 2026-06-30
Drought3121016101996 to 2026-06-30
Earthquake000000Storm Events does not record earthquakes; the USGS earthquake catalog is the source.
Hail5100001955 to 2026-06-30
Heat Wave6603001996 to 2026-06-30
Hurricane0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Ice Storm0000111996 to 2026-06-30No Storm Events records of this type; 1 federal declared incident (see declarations table)
Inland Flooding4100921996 to 2026-06-30
Landslide14716721996 to 2026-06-30
Lightning0000001996 to 2026-06-30No recorded events, 1996 to 2026-06-30, NOAA NCEI Storm Events
Strong Wind1991211193111955 to 2026-06-30Includes 186 High Wind and 12 Strong Wind records.
Tornado0000001950 to 2026-06-30No recorded events, 1950 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
Wildfire25916111996 to 2026-06-30
Winter Weather94831526206521996 to 2026-06-30

Notable Storm Events records

Sources: 1, 6, 7

DateEvent typeMagnitude or extentDamagenominal dollarsDeaths, injuriesdirect onlyLocationFlagsWhy listed
2026-02-15Avalanche$0 property; $0 crops (zone total, 2026 dollars)9, 0NWS zone CAZ072 (GREATER LAKE TAHOE AREA), zone-levelnew since last plan; within last 5 yearsdeaths or injuries recorded
2025-06-18Cold/Wind Chill$0 property; $0 crops (zone total, 2025 dollars)3, 0NWS zone CAZ069 (WEST SLOPE NORTHERN SIERRA NEVADA), zone-levelnew since last plan; within last 5 yearsdeaths or injuries recorded
2022-09-04Excessive Heat$0 property; $0 crops (zone total, 2022 dollars)0, 0NWS zone CAZ069 (WEST SLOPE NORTHERN SIERRA NEVADA), zone-levelnew since last plan; within last 5 yearsB1-c worst recorded: Excessive Heat, Heat
2021-10-08Drought$0 property; $0 crops (zone total, 2021 dollars)0, 0NWS zone CAZ069 (WEST SLOPE NORTHERN SIERRA NEVADA), zone-levelnew since last plan; within last 5 yearsB1-c worst recorded: Drought
2017-02-20High Wind173 kt (199 mph) measured gustproperty not reported; $0 crops (zone total, 2017 dollars)0, 0NWS zone CAZ069 (WEST SLOPE NORTHERN SIERRA NEVADA), zone-levelB1-c worst recorded: High Wind and Strong Wind
2015-09-09Wildfire$0 property; $0 crops (zone total, 2015 dollars)2, 1NWS zone CAZ069 (West Slope Northern Sierra Nevada), zone-leveldeaths or injuries recorded
2015-07-20Hail1.75 in$5,000 property; $0 crops (2015 dollars)0, 0LAKE ALPINEB1-c worst recorded: Hail
2007-06-24Wildfire$500,000,000 property; crops not reported (zone total, 2007 dollars)0, 3NWS zone CAZ072 (GREATER LAKE TAHOE AREA), zone-levelB1-c worst recorded: Wildfire
2005-12-31Flood$1,000,000 property; crops not reported (2005 dollars)0, 0WOODFORDSB1-c worst recorded: Flash Flood, Flood, Lakeshore Flood
2005-12-22Debris Flow$2,000 property; crops not reported (zone total, 2005 dollars)0, 0NWS zone CAZ072 (E NEVADA/E PLACER/E EL DORADO/NE ALPINE), zone-levelB1-c worst recorded: Debris Flow
2002-04-15Heavy Snow$500,000 property; crops not reported (zone total, 2002 dollars)0, 4NWS zone CAZ072 (GREATER LAKE TAHOE AREA), zone-levelB1-c worst recorded: Winter Storm, Heavy Snow, Blizzard, Lake-Effect Snow, Winter Weather, Sleet
1997-01-13Cold/Wind Chilldamage not reported0, 0NWS zone CAZ072 (GREATER LAKE TAHOE AREA), zone-levelB1-c worst recorded: Cold/Wind Chill, Extreme Cold/Wind Chill

The full list is in the Excel file, sheet "B1-d Storm Events history" (1,257 rows).

Location is the place NOAA recorded, as written in its data; it need not be a jurisdiction in this plan.

Local data needed: state-declared emergencies, from your state emergency management agency (federal data do not include them).

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

Supports FEMA checklist item B1-e: probability of future events

Probability: FEMA annualized frequency and descriptor per hazard

Sources: 5, 6

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
Avalanche0.333events per yearabout 1 in 3 yearsLikelyFEMA annualized frequency (modeled)101994 to 2023 (30 years)see B1-f
Cold Wave0event-days per yearnone modeledLikelyStorm Events event-days in 5 of 30 years, 1996 to 2025 (16.7%)02005-11-12 to 2024-11-12 (19 years)countywideNRI models no cold wave event-days here (2005-11-12 to 2024-11-12, 19 years); Storm Events has a record in 5 of 30 years. The descriptor comes from Storm Events, which records events NRI's definition leaves out.
Drought79.8event-days per yearabout 79.8 days per yearLikelyStorm Events event-days in 4 of 30 years, 1996 to 2025 (13.3%)2,0162000 to 2025 (25.25 years; D3 and D4 only)countywide
Earthquake0.0391annual probability at a locationchance a given location in the county has at least minor-damage shaking in a year: 3.91%not shownmodeledsee B1-fNo descriptor (Storm Events does not record earthquakes).
Hail0.153events per yearabout 1 in 7 yearsLikelyFEMA annualized frequency (modeled)5.8 (modeled)1986 to 2023 (38 years)countywide
Heat Wave1.29event-days per yearabout 1.29 days per yearLikelyStorm Events event-days in 3 of 30 years, 1996 to 2025 (10%)13.32005-11-12 to 2024-11-12 (19 years)countywide
Hurricaneevents per year1851 to 2024 (Atlantic); 1949 to 2024 (Pacific)see B1-fNot Applicable in NRI for this county; no descriptor.
Ice Stormevent-days per year1946-12-31 to 2014-02-12 (67 years)countywideNot Applicable in NRI for this county; no descriptor.
Inland Flooding0.107event-days per yearabout 0.107 days per yearLikelyStorm Events event-days in 3 of 30 years, 1996 to 2025 (10%)31996 to 2023 (28 years)see B1-f
Landslide2.09events per year (modeled)about 2.09 per yearHighly likelyFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Lightning21days per year with a strikeabout 21 days per yearHighly likelyFEMA annualized frequency (modeled)not shown1995 to 2023 (29 years; CONUS)countywide
Strong Wind0.104events per yearabout 1 in 10 yearsLikelyFEMA annualized frequency (modeled)41986 to 2023 (38 years)countywide
Tornado0.02events per yearabout 1 in 50 yearsPossibleFEMA annualized frequency (modeled)not shown1950 to 2023 (EF2+); 1986 to 2023 (EF0-1)see B1-f
Volcanic Activity0.0007annual probabilityabout 1 in 1,429 yearsUnlikelyFEMA annualized frequency (modeled)not shownmodeledsee B1-f
Wildfire0.0102annual probability at a locationchance a given location in the county burns in a year: 1.02%LikelyStorm Events records in 13 of 30 years, 1996 to 2025 (43.3%)not shownmodeledsee B1-f
Winter Weather39event-days per yearabout 39 days per yearHighly likelyStorm Events event-days in 30 of 30 years, 1996 to 2025 (100%)7412005-11-12 to 2024-11-12 (19 years)countywide

FEMA annualized frequency (modeled) is the National Risk Index v1.20 (December 2025) estimate of how often a hazard affects this county in a year; it is not recorded events divided by years, and its unit differs by hazard (events, event-days, or days with a lightning strike per year). For earthquake, wildfire, coastal flooding and tsunami the value is the chance (or number of events) at a location in the county, not across the county, so no "1 in N years" is given and the descriptor comes from Storm Events where it has a record (none for earthquake). The Methods page gives each hazard's method, from FEMA's National Risk Index Technical Documentation v1.20.

Where NRI gives event-days, the descriptor comes from the share of years with a Storm Events record; NRI's source records more events, so the two differ.

Descriptor scale used in this packet (defined per unit)

Sources: 5, 6

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

Intensity bands: historical frequency (Storm Events)

Source: 6

HazardBandYearsEventscounty-coded recordsYears in periodEvents per yearevents / years
Hail1.00-1.99 in1996 to 20254300.133
Hail2.00 in+1996 to 20250300
Thunderstorm Wind (counted as NRI Strong Wind)50-64 kt1996 to 20250300
Thunderstorm Wind (counted as NRI Strong Wind)65 kt+1996 to 20250300
Thunderstorm Wind (counted as NRI Strong Wind)unmeasured or below 50 kt1996 to 20251300.0333
TornadoEF0-11996 to 20250300
TornadoEF2-31996 to 20250300
TornadoEF4-51996 to 20250300
Tornadounrated (EFU)1996 to 20250300

The bands show how often events of each severity were recorded in this county, to profile how severe events have been (FEMA's probability item asks for the range of intensities).

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.

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 (https://resilience.climate.gov/).

Supports FEMA checklist item B1-f: hazards that vary across jurisdictions

NRI risk score of the county's single census tract

Source: 5

HazardTract scoreNRI score, 0 to 100Rating
Avalanche88.1Relatively Moderate
Cold WaveNo Rating
DroughtNo Rating
Earthquake84.0Relatively Moderate
Hail27.9Very Low
Heat Wave6.7Very Low
HurricaneNot Applicable
Ice StormNot Applicable
Inland Flooding90.5Relatively High
Landslide96.5Relatively Moderate
Lightning49.9Relatively Moderate
Strong Wind59.0Relatively Moderate
Tornado1.6Very Low
Volcanic Activity41.2Very Low
Wildfire99.2Very High
Winter Weather99.2Very High

The score ranks a tract against all U.S. tracts (100 = highest). The rating is FEMA's category for the tract's risk value, computed differently, so the two can disagree.

Each jurisdiction (starting figures from federal data)

Sources: 1, 3, 4, 6

JurisdictionTypePlan statusRepetitive lossFMA RL and SRL (44 CFR 77.2); repeat-flood, any definitionPublic Assistance to this jurisdictionFEMA records matched by applicant name; federal share obligated, nominal dollarsEvent records naming this placeall years; since its plan
Alpine CountyCountyExpired on 2023-08-16FMA RL 0, SRL 0; any 0$1,124,757.770 total; 0 since its plan

Repetitive-loss counts are for whole NFIP communities, which can extend beyond this county (see the note in B2-c).

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

County Public Assistance in B1-d also includes applicants filed under the county that are not jurisdictions in this plan (for example state agencies, special districts and nonprofits), so the jurisdiction rows add up to less.

Supports FEMA checklist items B2-a and B2-b: vulnerability and potential impacts

Local data needed

The table below gives county-level starting figures; the plan describes impacts for each jurisdiction and its own assets.

  • Critical facilities and lifelines per hazard
  • A problem statement per jurisdiction 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

Sources: 1, 2, 3, 5, 6, 7

HazardBuilding exposuremodeled dollarsAgriculture exposuremodeled dollarsPopulation exposedpeopleEAL buildingsmodeled dollars per yearEAL agriculturemodeled dollars per yearCost of expected deaths and injuriesFEMA's dollar value per year, not property damageEAL as % of exposurebuildings; agriculture where notedStorm Events damage since 2018-08-17county-coded records, property plus crops, nominal dollarsZone-level damage since planproperty plus crops, reported for the zonePublic Assistance since plannominal dollars; see noteNote
Avalanche$1,039,853n/a10$36n/a$1,825,6000.0035%$0
Cold Wave$0$00$0$0$0$0building exposure is 0 in NRI
Droughtn/a$0n/an/a$0n/a$0agriculture exposure is 0 in NRI
Earthquake$1,548,846,344n/a1,204$300,903n/a$8,3280.0194%
Hail$967,195,880$2,556,3181,198$230$259$975under 0.0001%
Heat Wave$967,195,880$2,556,3181,198$5$34$4,786under 0.0001%$0
HurricaneNot Applicable in NRI for this county
Ice Storm$71,887.38Not Applicable in NRI for this county
Inland Flooding$965,031,911$33$1,392,459under $1$128n/a (see note)$0$731,459.32NRI 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.
Landslide$144,134,782n/a86$475n/a$3,6360.00033%$0$731,459.32
Lightning$967,195,880n/a1,198$859n/a$9,192under 0.0001%
Strong Wind$967,195,880$2,556,3181,198$4,962$149$14,9220.000513%$280,000$71,887.38Storm Events damage since the plan includes 5 zone-level High Wind records ($280,000): a NOAA non-thunderstorm wind type, outside NRI's Strong Wind definition.
Tornado$967,195,880$2,556,3181,198$181$2$13under 0.0001%
Volcanic Activity$967,195,880n/a1,198under $1n/aunder $1under 0.0001%
Wildfire$400,324,120$2,404,426815$1,129,823$76$25,8380.282%$0no Public Assistance recorded (1 declaration)
Winter Weather$967,195,880$2,556,3181,198$6,741under $1$54,6920.000697%$1,000$731,459.32

Totals since 2018-08-17 (Storm Events through 2026-06-30): 9 county-coded records, 8 with a damage value recorded (including $0), $0; 481 zone-level records, 411 with a damage value recorded (including $0), $281,000 reported for the zone; Public Assistance: $731,459.32 on 4 counted declarations, 2 of them with Public Assistance.

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 does not add up to the total; the unit total counts each declaration once.

NRI computes earthquake exposure on its own basis, so it exceeds the county building value in B2-a.

Supports FEMA checklist item B2-a: vulnerability (county context)

County context

Source: 5

MeasureValue
Population1,198
Building value (total, not at risk)$967,195,880
Agriculture value (total, not at risk)$2,556,318
NRI risk rating (all hazards)Very Low
Expected annual loss, buildings and agriculture, all hazards$2,837,196
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)$1,948,111
Social vulnerability ratingRelatively Moderate
Community resilience ratingRelatively Moderate
NRI versionDecember 2025

FEMA's all-hazard expected annual loss adds buildings, agriculture and population equivalence; this table gives the property part and the population-equivalence part as separate rows.

Social vulnerability: higher means people are more likely to be harmed and slower to recover. Community resilience: lower means the community is less able to recover. High social vulnerability and low resilience both raise the NRI risk rating.

Supports FEMA checklist item B2-c: repetitive loss properties

Repetitive loss in this county, both definitions

Sources: 1, 4

DefinitionPropertiesSevere repetitive lossProperties
Repetitive loss, FMA definition (44 CFR 77.2)0Severe repetitive loss, FMA definition (44 CFR 77.2)0
Repetitive loss, NFIP insurance definition0Severe repetitive loss, NFIP insurance definition0

The state NFIP coordinator's list, the source FEMA's Handbook names, often uses the NFIP insurance definition (second row).

Repeat-flood properties: county and state-level rows

Sources: 1, 4

ScopeRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
County total0000000
Statewide, no county in FEMA's file0130410

The statewide row counts properties FEMA's file gives with no county in this state; they are listed for reference and are not in this county's counts.

Repeat-flood properties by jurisdiction in the plan (NFIP community)

Sources: 1, 4

JurisdictionNFIP community IDRL, FMApropertiesSRL, FMApropertiesRL, NFIPpropertiesSRL, NFIPpropertiesAny categorypropertiesMitigatedpropertiesCurrently insuredproperties
Alpine County0606320000000

Counts by occupancy group for each jurisdiction are in the Excel file, sheet "B2-c Jurisdictions".

Jurisdiction 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 jurisdiction row, while the county table counts only its part in this county.

County repeat-flood properties by occupancy group: 0 in every occupancy group.

Sources: 1, 4

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. NFIP repetitive loss (the FEMA insurance definition) is 2 or more claims over $1,000 in 10 years, and a property can leave that group once it is mitigated. Also shown: NFIP severe repetitive loss, any category, mitigated and currently insured. The Methods page gives the OpenFEMA field details.

Counts are aggregates of FEMA's public NFIP Multiple Loss Properties file (FEMA's data date 2026-08-02; file version 2026-08-04). No property is identified. County assignment is FEMA's geocode.

In this county 0 properties are FMA repetitive loss but not NFIP repetitive loss, and 0 properties are NFIP repetitive loss but not FMA repetitive loss.

Exact counts; no count suppression.

Sources

Tables cite these sources by number. The full list, for the plan's bibliography (FEMA review item A4-a):

  1. FEMA, OpenFEMA HazardMitigationPlanStatuses v1, version 2026-09-29T134039Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/HazardMitigationPlanStatuses (API)
  2. FEMA, OpenFEMA DisasterDeclarationsSummaries v2, version 2026-09-29T162832Z, pulled 2026-09-30, https://www.fema.gov/api/open/v2/DisasterDeclarationsSummaries (API)
  3. FEMA, OpenFEMA PublicAssistanceFundedProjectsSummaries v1, version 2026-09-29T150754Z, pulled 2026-09-30, https://www.fema.gov/api/open/v1/PublicAssistanceFundedProjectsSummaries (API)
  4. FEMA, OpenFEMA NfipMultipleLossProperties v1, version 2026-08-04T164045Z, pulled 2026-09-30, 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 2026-09-30, 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 2026-09-30, 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 2026-09-30, 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 2026-09-30, 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 (used to match place names and codes; no table prints its values)

What this packet is and what the plan adds

This packet is the federal data for the plan's risk assessment (the summary on page 1 says how it is organized); the plan and FEMA's review decide whether each item is met.

The plan adds what only the community has: local data on assets, critical facilities, development and each jurisdiction's impacts; local hazard history, including state-declared emergencies; the mitigation strategy; and adoption.

How the federal data are built: National Risk Index values are FEMA's model, not counts of events. Storm Events is more complete from 1996; zone-level records are placed by forecast zone, not by location in the county. Public Assistance for a jurisdiction is matched by applicant name. The Methods page gives every rule and the known edge cases.

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).

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). Alpine County, CA: risk-assessment baseline packet, release 2026-10 (data as of 2026-09-30; County FIPS 06003). Automated baseline. https://hazardplain.org/ca/06003/ 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: [email protected]