Enter any address in Petroleum County, Montana to see its FEMA flood zone
Flash flooding from thunderstorms is the dominant flood character in Petroleum County. Between 1993 and 2023, NOAA Storm Events data recorded 17 flood events and 7 flash flood events. Recent occurrences include flash flooding in June 2023 due to heavy rainfall and flooding in July 2022 from severe thunderstorms.
Residents in areas designated as Special Flood Hazard Areas (SFHAs) by FEMA should pay the most attention to flood risk. These zones, which include A, AE, and VE zones, are identified as having a 1% or greater annual chance of flooding.
Summary generated from NOAA storm narratives and NFIP claim data for this county. Not predictive.
1 NOAA storm reports from this county describe what happened, in the words of the meteorologists who were there.
Petroleum County, Montana has recorded 24 flood-related events since 1996 according to NOAA's Storm Events Database, including 7 flash floods and 17 river or area floods. The county has received 12 federal disaster declarations, 4 of which involved flooding or coastal storms. Enter any address above to check its FEMA flood zone designation.
FEMA Disaster Declarations (1986–2024)
Source: OpenFEMA Disaster Declarations Summaries.
| Declaration | Type | Date |
|---|---|---|
| Severe Winter Storm And Flooding | Severe Storm | May 6, 2024 |
| Flooding | Flood | Jun 1, 2023 |
| Covid-19 | Biological | Jan 20, 2020 |
| Covid-19 Pandemic | Biological | Jan 20, 2020 |
| Flooding | Flood | Apr 12, 2018 |
| Lodgepole Fire Complex | Fire | Jul 20, 2017 |
| Severe Storms, Straight-line Winds, And Flooding | Severe Storm | Aug 21, 2014 |
| Flooding | Flood | May 19, 2013 |
| Severe Storms And Flooding | Severe Storm | Apr 4, 2011 |
| Hurricane Katrina Evacuation | Hurricane | Aug 29, 2005 |
NOAA Storm Events Database (1996–2025)
Source: NOAA National Weather Service Storm Events Database.
| Type | Date | Damage |
|---|---|---|
| Flash Flood | Jun 23, 2023 | 0.00K |
| Flood | Jul 4, 2022 | 0.00K |
| Flood | Aug 26, 2021 | 0.00K |
| Flood | May 27, 2019 | 0.00K |
| Flood | Mar 12, 2018 | 0.00K |
| Flood | Jun 1, 2018 | 0.00K |
| Flood | Oct 4, 2016 | 0.00K |
| Flood | Aug 23, 2014 | 515.00K |
| Flood | Jun 3, 2013 | 0.00K |
| Flood | May 23, 2011 | 0.00K |
Flash Flood — Jun 23, 2023
An upper level low moving to the south along the Montana-Wyoming border, generated heavy rainfall across southern parts of northeast Montana, with some flash flooding impacts recorded in Petroleum County.
Flood — Jul 4, 2022
Shortwave moved through the southwesterly flow aloft that's been parked over the area this week and set off another round of severe thunderstorms over the area this afternoon into the overnight hours.
Flood — Aug 26, 2021
A mid-level disturbance moving through the region, combined with favorable winds to generate and support multiple severe thunderstorms in Garfield and Petroleum Counties along with some flooding for Petroleum County.
Flood — May 27, 2019
A stalled storm track prolonged at moderate to heavy rainfall for many hours across most of southern Petroleum County.
Flood — Mar 12, 2018
The spring thaw through the central Montana region allowed ice to break up along the Musselshell River. The meandering nature of the river and the sudden warm up in temperatures resulted in a brief period of ice jam flooding near the Mosby area of southeastern Petroleum County and southwestern Garfield County.
Source: NOAA National Weather Service Storm Events Database.
FEMA assigns flood zone designations to areas in Petroleum County, Montana:
AE High Risk — 1% annual chance of flooding. Insurance required.
VE Very High Risk — Coastal flooding with wave action.
X (Shaded) Moderate Risk — 500-year floodplain.
X Low Risk — Outside major floodplains.
Properties in Petroleum County, Montana that are in FEMA-designated Special Flood Hazard Areas (zones A and V) with federally backed mortgages are required to carry flood insurance.
Even outside high-risk zones, flood insurance is recommended. From 2014 to 2024, nearly one-third of NFIP claims came from outside the high-risk Special Flood Hazard Area.
Visit FloodSmart.gov to find an agent and get a quote.