Alert archive / Montana / Flash Flood Warnings in 2010

Flash Flood Warning 1, NWS Great Falls, MT

June 20, 2010Cascade County, Judith Basin County, Montana

NWS Great Falls, MT issued this flash flood warning at Jun 20, 2010, 3:09 PM MDT for Cascade County, Judith Basin County, Montana. It was in force for 115 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
Jun 20, 2010, 3:09 PM MDT (21:09 UTC)
Expired
Jun 20, 2010, 5:04 PM MDT
In force
115 min
Issued by
NWS Great Falls, MT
Area
Storm-based polygon
Flood severity
None

Counties Cascade County, MT, Judith Basin County, MT

The radar

The Great Falls radar (KTFX), 54 km from the middle of the area, began a volume at 21:12 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

Great_falls, MT (KTFX), launched 12:00Z, 9.2 hours before the alert went out and 35 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, Great_falls, MT at 12:00Z on 2010-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 9 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, Great_falls, MT at 12:00Z on 2010-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -17 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
9 J/kg
Mixed-layer CIN
-110 J/kg
Mixed-layer LCL
1121 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
-17 m²/s²
0-3 km storm-relative helicity
32 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
Jun 19, 7:00 PM MDTSpecial Weather StatementTFXCascade45 min
Jun 20, 2:57 PM MDTSpecial Weather StatementTFXGallatin48 min
Jun 20, 3:02 PM MDTSpecial Weather StatementTFXJudith Basin43 min
Jun 20, 3:17 PM MDTSpecial Weather StatementTFXMeagher43 min
Jun 20, 4:02 PM MDTSevere Thunderstorm WarningTFXBroadwater, Jefferson, Lewis and Clark43 min
Jun 20, 4:16 PM MDTSevere Thunderstorm WarningTFXJudith Basin59 min
Jun 20, 4:44 PM MDTSevere Thunderstorm WarningTFXBroadwater, Lewis and Clark, Meagher61 min
Jun 20, 4:44 PM MDTSevere Thunderstorm WarningTFXChouteau, Fergus, Judith Basin46 min
Jun 20, 5:06 PM MDTSpecial Weather StatementTFXFergus39 min
Jun 20, 5:25 PM MDTSevere Thunderstorm WarningTFXChouteau, Fergus, Judith Basin65 min
Jun 20, 5:44 PM MDTSpecial Weather StatementTFXFergus46 min

Nearby

Flash Flood Warnings in Montana, 2010Every flash flood warning in 2010

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.