Alert archive / Montana / Flash Flood Warnings in 2025

Flash Flood Warning 3, NWS Glasgow, MT

July 20, 2025Prairie County, Montana

NWS Glasgow, MT issued this flash flood warning at Jul 20, 2025, 6:35 PM MDT for Prairie County, Montana. It was in force for 83 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
Jul 20, 2025, 6:35 PM MDT (00:35 UTC)
Expired
Jul 20, 2025, 7:58 PM MDT
In force
83 min
Issued by
NWS Glasgow, MT
Area
Storm-based polygon
Flood severity
None

County Prairie County, MT

The radar

The Glasgow radar (KGGW), 176 km from the middle of the area, began a volume at 00:34 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 nearest sounding before it

Rapid City, SD (KUNR), launched 00:00Z, 0.6 hours before the alert went out and 366 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.

Skew-T log-pSkew-T log-p diagram, Rapid City, SD at 00:00Z on 2025-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1882 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Rapid City, SD at 00:00Z on 2025-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -10 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1882 J/kg
Mixed-layer CIN
-110 J/kg
Mixed-layer LCL
1104 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
-10 m²/s²
0-3 km storm-relative helicity
181 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.7

Open this sounding in Storm Lab

The office that day

Everything else NWS Glasgow, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 20, 6:10 PM MDTSevere Thunderstorm Warning Destructive damage threatGGWPrairie, Wibaux65 min
Jul 20, 6:29 PM MDTSpecial Weather StatementGGWRoosevelt61 min
Jul 20, 6:41 PM MDTSpecial Weather StatementGGWRichland64 min
Jul 20, 6:42 PM MDTSevere Thunderstorm WarningGGWWibaux52 min
Jul 20, 6:45 PM MDTSpecial Weather StatementGGWRichland60 min
Jul 20, 7:05 PM MDTSpecial Weather StatementGGWSheridan55 min

Nearby

Flash Flood Warnings in Montana, 2025Every flash flood 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.