Alert archive / North Dakota / Severe Thunderstorm Warnings in 2025
Severe Thunderstorm Warning 249, NWS Bismarck, ND
NWS Bismarck, ND issued this severe thunderstorm warning at Aug 17, 2025, 1:59 AM MDT for Grant County, Sioux County, North Dakota. It was in force for 61 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Aug 17, 2025, 1:59 AM MDT (07:59 UTC)
- Expired
- Aug 17, 2025, 3:00 AM MDT
- In force
- 61 min
- Issued by
- NWS Bismarck, ND
- Area
- Storm-based polygon
- Hail
- 0.88 in
- Wind
- 60.0 mph
Counties Grant County, ND, Sioux County, ND
The radar
The Bismarck radar (KBIS), 74 km from the middle of the area, began a volume at 07:59 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Aug 16, 9:59 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
The nearest sounding before it
Bismarck Municip, ND (KBIS), launched 00:00Z, 8.0 hours before the alert went out and 77 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 1908 J/kg
- Mixed-layer CIN
- -107 J/kg
- Mixed-layer LCL
- 931 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 131 m²/s²
- 0-3 km storm-relative helicity
- 109 m²/s²
- Significant tornado parameter
- 0.3
- Supercell composite
- 3.3
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Bismarck, ND wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 17, 12:14 AM MDT, 1 hour 45 minutes earlier.
Area forecast discussion, Aug 17, 12:14 AM MDT, 1 hour 45 minutes before
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</html>Hazardous weather outlook, Aug 17, 12:06 AM MDT, 1 hour 53 minutes before
Hazardous Weather Outlook National Weather Service Bismarck ND 106 AM CDT Sun Aug 17 2025 NDZ001-009-017>020-031>037-040>048-050-051-180615- Divide-Williams-McKenzie-Dunn-Mercer-Oliver-Golden Valley- Billings-Stark-Morton-Burleigh-Kidder-Stutsman-Slope-Hettinger- Grant-Bowman-Adams-Sioux-Emmons-Logan-La Moure-McIntosh-Dickey- 106 AM CDT Sun Aug 17 2025 /1206 AM MDT Sun Aug 17 2025/ This Hazardous Weather Outlook is for portions of northwest North Dakota, south central North Dakota, southeast North Dakota, and southwest North Dakota. .DAY ONE...Tonight Isolated strong to severe thunderstorms are possible tonight. Expected hazards include hail up to the size of quarters, damaging winds as high as 60 mph, and torrential rainfall. .DAYS TWO THROUGH SEVEN...Sunday through Friday Isolated strong to severe thunderstorms are possible across western North Dakota Sunday evening and night. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report severe weather and excessive rain amounts to the National Weather Service at 800-247-0212 or on social media pages. NDZ002>005-010>013-021>023-025-180615- Burke-Renville-Bottineau-Rolette-Mountrail-Ward-McHenry-Pierce- McLean-Sheridan-Wells-Foster- 106 AM CDT Sun Aug 17 2025 This Hazardous Weather Outlook is for portions of north central North Dakota, northwest North Dakota, south central North Dakota, and southeast North Dakota. .DAY ONE...Tonight The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Sunday through Friday The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotters are encouraged to report excessive rain amounts to the National Weather Service at 800-247-0212 or on social media pages. NH
The office that day
Everything else NWS Bismarck, ND issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 17, 2:56 AM MDT | Severe Thunderstorm Warning | BIS | Emmons, Grant, Morton, Sioux | 64 min |
| Aug 17, 3:31 AM MDT | Severe Thunderstorm Warning | BIS | Emmons, Sioux | 29 min |
| Aug 17, 3:57 AM MDT | Severe Thunderstorm Warning | BIS | Emmons, Logan, McIntosh | 48 min |
| Aug 17, 4:43 AM MDT | Special Weather Statement | BIS | Kidder, Logan, McIntosh | 32 min |
| Aug 17, 4:55 AM MDT | Special Weather Statement | BIS | Burleigh | 35 min |
| Aug 17, 5:17 AM MDT | Special Weather Statement | BIS | Dickey | 43 min |
| Aug 17, 9:29 AM MDT | Special Weather Statement | BIS | Dickey | 31 min |
| Aug 17, 9:57 AM MDT | Special Weather Statement | BIS | Dickey | 33 min |
Nearby
Severe Thunderstorm Warnings in North Dakota, 2025Every severe thunderstorm warning in 2025
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.