Alert archive / Montana / Flash Flood Warnings in 2009

Flash Flood Warning 1, NWS Glasgow, MT

August 7, 2009Dawson County, Richland County, Wibaux County, Montana

NWS Glasgow, MT issued this flash flood warning at Aug 7, 2009, 10:36 PM MDT for Dawson County, Richland County, Wibaux County, Montana. It was in force for 4 hr. 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 7, 2009, 10:36 PM MDT (04:36 UTC)
Expired: Aug 8, 2009, 2:30 AM MDT
In force: 4 hr
Issued by: NWS Glasgow, MT
Area: Storm-based polygon
Flood severity: None

Counties Dawson County, MT, Richland County, MT, Wibaux County, MT

The radar

The Glasgow radar (KGGW), 181 km from the middle of the area, began a volume at 04:37 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, 4.6 hours before the alert went out and 386 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1562 J/kg
Mixed-layer CIN: -72 J/kg
Mixed-layer LCL: 1737 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 40 m²/s²
0-3 km storm-relative helicity: 202 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 9.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Glasgow, MT wrote its last area forecast discussion before this flash flood warning went out at Aug 7, 2:45 PM MDT, 7 hours 51 minutes earlier.

Area forecast discussion, Aug 7, 2:45 PM MDT, 7 hours 51 minutes before

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Hazardous weather outlook, Aug 7, 3:20 AM MDT, 19 hours 16 minutes before

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        The site you requested is temporarily down for maintenance or an unexpected outage.
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        Please try again in a few minutes.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 7, 8:46 PM MDT	Severe Thunderstorm Warning	GGW	Dawson, Prairie, Wibaux	37 min

Nearby

Flash Flood Warnings in Montana, 2009 Every flash flood warning in 2009

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.