Sweet Grass County, Montana: hazard history

FEMA declared 10 disasters that named Sweet Grass County between 1997 and 2025.

Most recent declarations

• DR-4902 2025 · Straight-Line Winds · Severe Winter Storm And Straight-line Winds
• DR-4655 2022 · Flood · Severe Storm And Flooding
• EM-3476 2020 · Biological · Covid-19
• DR-4508 2020 · Biological · Covid-19 Pandemic
• DR-1996 2011 · Severe Storm · Severe Storms And Flooding
• FM-2671 2006 · Fire · Derby Fire
• EM-3253 2005 · Hurricane · Hurricane Katrina Evacuation
• FM-2488 2003 · Fire · Mt-hobble Fire-08/07/2003
• DR-1340 2000 · Fire · Wildfires
• DR-1183 1997 · Severe Storm · Severe Storms,ice Jams, Snow Melt, Flooding

Not counted above: 31 statewide declarations, which covered every county in Montana. A declaration is a decision to send federal help, not a measure of how bad an event was. Records run from 1953. Source: FEMA OpenFEMA Disaster Declarations Summaries.

Records start in 1996. Damage is NOAA's estimate at the time, in nominal dollars, and is often rounded; it is not insurance claims data. A storm that crossed two NOAA zones in this county is recorded, and counted, once per zone. A storm filed against a forecast zone is counted in every county that zone covers, with the whole storm's damage; do not add these figures across counties.

NOAA storm event records in Sweet Grass County each year. The busiest year was 2021, with 76 records.

Years with no record are left out of the table, not shown as zero.

Costliest records

1. Flood · May 20, 2011$4.0M
   NOAA name: Sweet Grass County · NOAA record 308816

Deadliest records

1. Avalanche · Jan 3, 20101 death
   NOAA name: NWS forecast zone · NOAA record 212908
2. Avalanche · Dec 31, 20111 death
   NOAA name: NWS forecast zone · NOAA record 354739
3. Avalanche · Feb 22, 20121 death
   NOAA name: NWS forecast zone · NOAA record 358926
4. Avalanche · Mar 11, 20141 death
   NOAA name: NWS forecast zone · NOAA record 512841
5. Avalanche · Nov 26, 20141 death
   NOAA name: NWS forecast zone · NOAA record 548127

Each line is one NOAA record, linked to its page at NOAA. One large storm can appear more than once if NOAA recorded it in several zones of this county. Dollars are nominal.

The National Flood Insurance Program paid $194K on 10 claims in Sweet Grass County from 1997 to 2022.

A count of claims, not a rate: NFIP publishes no count of insured homes beside it, and most flood damage is uninsured. Nominal dollars. Records run from 1978 to 2024; claims filed without a county code are not on any county page. Source: FEMA OpenFEMA FIMA NFIP Redacted Claims.

A hazard vulnerability analysis rates each hazard for probability, impact, preparedness and response. Probability is the one column the county’s federal record can fill — NCEI storm events from 1996 to 2026 and FEMA declarations naming the county — and this is what it says for a facility here, on the 0–3 scale of the all-hazards structure surveyors expect. The other six columns are the facility’s own judgment about its building, and Calchis leaves them blank.

A dash means the record does not speak to that hazard; it is not a zero. Whether a finished document satisfies the CMS Emergency Preparedness Rule is the facility’s finding and its surveyor’s. Complete the HVA for a facility in Sweet Grass County — the technological, human and hazardous-materials rows, the six facility columns, the approval and the printed document — or read the sample analysis on that page first.

• Every figure is counted from public federal records held by Calchis: NOAA NCEI Storm Events, FEMA OpenFEMA Disaster Declarations, and FEMA NFIP claims. Nothing is modeled or estimated.
• NOAA files some events against a county and others against an NWS forecast zone, and publishes a code for both. Records are counted as Sweet Grass County by that code — county records by the county's own FIPS code, zone records through the National Weather Service's published list of which counties each zone covers. No name matching is involved. Of 882 records, 175 were filed against this county and 707 against a forecast zone covering it. A zone storm is counted in every county its zone covers, and its damage figure is the whole storm's, not this county's share — NOAA does not publish that split. So these figures describe this county; they must not be added up across counties. Left out: 21% of Montana's NOAA records, which are marine zones or zones NWS does not map to a county.
• Counts last rebuilt from the source records on Sep 15, 2026.
• This county's NOAA record is short (under 100 records, under 10 with damage, or under 10 years), so this page is not offered to search engines. It is still accurate.