Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 145, NWS Glasgow, MT

September 4, 2002Phillips County, Valley County, Montana

NWS Glasgow, MT issued this severe thunderstorm warning at Sep 4, 2002, 11:53 PM MDT for Phillips County, Valley County, Montana. It was in force for 67 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Sep 4, 2002, 11:53 PM MDT (05:53 UTC)
Expired
Sep 5, 2002, 1:00 AM MDT
In force
67 min
Issued by
NWS Glasgow, MT
Area
Counties, with a storm outline in the text

Counties Phillips County, MT, Valley County, MT

The radar

The Glasgow radar (KGGW), 51 km from the middle of the area, began a volume at 05:55 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.

What was reported inside it

TimeReportWhereRemark
Sep 5, 1:00 AM MDTThunderstorm Wind 52 MHinsdale, MT60 mph wind reported by spotter 15 miles northwest of Hinsdale.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 5.9 hours before the alert went out and 264 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 00:00Z on 2002-09-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 359 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 00:00Z on 2002-09-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -64 square meters per square second.19395878Sfc1 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
359 J/kg
Mixed-layer CIN
-127 J/kg
Mixed-layer LCL
2121 m above ground
0-6 km bulk shear
59 kt
0-1 km storm-relative helicity
-64 m²/s²
0-3 km storm-relative helicity
47 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

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 Glasgow, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 4, 8:15 PM MDT, 3 hours 38 minutes earlier.

Area forecast discussion, Sep 4, 8:15 PM MDT, 3 hours 38 minutes before
NORTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
815 PM MDT WED SEP 4 2002

.SHORT TERM...ISOLATED THUNDERSTORM OVER THE MISSOURI RIVER ON
GARFIELD AND PHILLIPS COUNTY LINE AT THIS TIME. THIS STORM APPEARS
TO BE AT THE NORTHERN END OF A SHORTWAVE OVER SOUTH CENTRAL MONTANA
THAT IS BRINGING CONVECTIVE ACTIVITY TO SE MONTANA. THIS WAVE IS
MOVING ALONG A FRONTAL BOUNDARY LOCATED OVER SOUTHERN MONTANA. LOOK
FOR THIS WAVE TO MOVE ACROSS ERN MONTANA OVERNIGHT AND COULD
EVENTUALLY BRING SOME STORMS TO SE PART OF FORECAST AREA. WITH
ANOTHER AREA OF STORMS OVER NW FERGUS COUNTY AND SW FLOW ALOFT
OVERRUNNING THE FRONTAL BOUNDARY...WILL MAINTAIN GOING FORECAST
WHICH HAS A CHANCE OF SHOWERS AND THUNDERSTORMS FOR THE ENTIRE AREA.
NO UPDATES PLANNED. FORRESTER

.LONG TERM...AVN EXTENDED CONTINUES SOUTHWEST FLOW OVER THE REGION
AS THE WEST COAST TROUGH MOVES NEAR SHORE.  PRECIP CONVEYOR CUTS OFF
THE TROPICAL CONNECTION BUT CONTINUED AFTERNOON SHOWERS REMAIN
POSSIBLE.  SHOWER POTENTIAL STARTS TO DECREASE ABOUT DAY 6 AND 7 BUT
IS TOO INDEFINITE TO MAKE CHANGES TO THE PRESENT CHANCE POPS.
EXPECT SEASONAL TEMPERATURES.  MCNULTY

KGGW BEB 062/085 054/078 054/074 79333443
     BBBB 053/076 051/073 052/075 053/063 8133333333
KGDV BBB 063/099 057/087 057/085 79223333
     BEBU 056/082 054/080 053/077 053/064 8144333333

.GGW...NONE.

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 4, 10:33 PM MDTSevere Thunderstorm WarningGGWPhillips57 min

Nearby

Severe Thunderstorm Warnings in Montana, 2002Every severe thunderstorm warning in 2002

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.