Alert archive / Montana / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 76, NWS Great Falls, MT

July 12, 2019Madison County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jul 12, 2019, 4:35 PM MDT for Madison County, Montana. It was in force for 40 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 12, 2019, 4:35 PM MDT (22:35 UTC)
Expired
Jul 12, 2019, 5:15 PM MDT
In force
40 min
Issued by
NWS Great Falls, MT
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Madison County, MT

The radar

The Great Falls radar (KTFX), 244 km from the middle of the area, began a volume at 22:38 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

Riverton, WY (KRIW), launched 12:00Z, 10.6 hours before the alert went out and 375 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, Riverton, WY at 12:00Z on 2019-07-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 37 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 12:00Z on 2019-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 49 square meters per square second.1939Sfc1 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
37 J/kg
Mixed-layer CIN
-306 J/kg
Mixed-layer LCL
2577 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
49 m²/s²
0-3 km storm-relative helicity
75 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 11, 6:32 PM MDTSpecial Weather StatementTFX28 min
Jul 11, 7:04 PM MDTSpecial Weather StatementTFXBroadwater41 min
Jul 11, 7:25 PM MDTSpecial Weather StatementTFX35 min
Jul 11, 7:33 PM MDTSpecial Weather StatementTFXFergus42 min
Jul 11, 7:39 PM MDTSpecial Weather StatementTFXBroadwater36 min
Jul 11, 7:51 PM MDTSpecial Weather StatementTFXMeagher39 min
Jul 11, 8:02 PM MDTSpecial Weather StatementTFXBroadwater28 min
Jul 11, 8:29 PM MDTSpecial Weather StatementTFXMeagher46 min
Jul 11, 8:53 PM MDTSevere Thunderstorm WarningTFXJudith Basin, Meagher37 min
Jul 11, 9:05 PM MDTSpecial Weather StatementTFXFergus25 min
Jul 11, 9:30 PM MDTSpecial Weather StatementTFXJudith Basin30 min
Jul 11, 9:36 PM MDTSpecial Weather StatementTFXFergus39 min
Jul 11, 9:58 PM MDTSpecial Weather StatementTFXFergus47 min
Jul 11, 10:29 PM MDTSevere Thunderstorm WarningTFXFergus31 min
Jul 12, 3:01 PM MDTSpecial Weather StatementTFXMadison14 min
Jul 12, 4:21 PM MDTSpecial Weather StatementTFXMadison39 min
Jul 12, 5:21 PM MDTSpecial Weather StatementTFXMadison9 min
Jul 12, 5:23 PM MDTSpecial Weather StatementTFXGallatin22 min
Jul 12, 5:45 PM MDTSpecial Weather StatementTFXGallatin30 min
Jul 12, 5:58 PM MDTSpecial Weather StatementTFX17 min

Nearby

Severe Thunderstorm Warnings in Montana, 2019Every severe thunderstorm warning in 2019

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.