Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 137, NWS Glasgow, MT

August 26, 2002Valley County, Montana

NWS Glasgow, MT issued this severe thunderstorm warning at Aug 26, 2002, 8:48 PM MDT for Valley County, Montana. It was in force for 57 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: Aug 26, 2002, 8:48 PM MDT (02:48 UTC)
Expired: Aug 26, 2002, 9:45 PM MDT
In force: 57 min
Issued by: NWS Glasgow, MT
Area: Counties, with a storm outline in the text

County Valley County, MT

The radar

The Glasgow radar (KGGW), 18 km from the middle of the area, began a volume at 02:50 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

Time	Report	Where	Remark
Aug 26, 8:55 PM MDT	Hail 0.75	Glasgow, MT

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

Bismarck Municip, ND (KBIS), launched 00:00Z, 2.8 hours before the alert went out and 481 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: 599 J/kg
Mixed-layer CIN: -113 J/kg
Mixed-layer LCL: 2538 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: -21 m²/s²
0-3 km storm-relative helicity: -36 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 Aug 26, 3:40 PM MDT, 5 hours 8 minutes earlier.

Area forecast discussion, Aug 26, 3:40 PM MDT, 5 hours 8 minutes before

NORTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
340 PM MDT MON AUG 26 2002

.SHORT TERM...
UPPER LOW OVER SASKATCHEWAN WILL DRIFT SLOWLY EAST AS ANOTHER UPPER
LOW DIGS INTO GREAT BASIN. MODELS IN DECENT AGREEMENT INTO WEDNESDAY
WITH AXIS BETWEEN LOWS DROPS SOUTHEAST ACROSS THE STATE. THIS WILL
SLOWLY SHIFT THE FOCUS FOR SHOWERS AND THUNDERSTORMS FROM NORTHERN
MONTANA TONIGHT TO SOUTHERN MONTANA ON WEDNESDAY. ETA DRIER THEN AVN
WITH NO PRECIP OVER CWA ON WEDNESDAY. GIVEN WET PATTERN THAT HAS
PERSISTED THROUGHOUT THE MONTH WILL HEDGE TOWARD THE SLIGHTLY WETTER
MODEL AND KEEP SLIGHT CHANCE POPS FOR MUCH OF NORTHERN ZONES ON
WEDNESDAY. SURFACE HIGH DROPPING OUT OF ALBERTA ON WEDNESDAY WILL
KEEP COOL TEMPERATURES OVER THE REGION.

BY THURSDAY...SASKATCHEWAN LOW MOVES EAST AND GREAT BASIN LOW BEGINS
TO DOMINATE. UPPER FLOW TURNS SOUTH AND AVN INDICATING FAIRLY STRONG
LOW LEVEL JET INTO EASTERN MONTANA. WARMER TEMPERATURES EXPECTED
ALONG WITH SLIGHT CHANCE OF THUNDERSTORMS.

.LONG TERM...
UPPER LOW LIFTS OUT OF GREAT BASIN ON FRIDAY WITH ANOTHER LOW
DROPPING INTO PACIFIC NORTHWEST. MEDIUM RANGE MODELS STILL TRYING TO
CUT OFF THIS LOW AS IT DIGS SOUTH INTO CALIFORNIA. THIS BRINGS MORE
WESTERLY FLOW INTO MONTANA FOR DRIER WEATHER. COOL TEMPERATURES
SHOULD CONTINUE WITH FLOW COMING ACROSS THE NORTH PACIFIC/GULF OF
ALASKA. EBERT

KGGW EBB 057/078 055/081 050/082 90333222
     BBBB 056/085 054/078 051/074 050/073 9022000000
KGDV BBB 054/081 057/081 051/085 90223332
     BBBB 056/085 055/082 054/078 050/075 9023000000

.GGW...NONE

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 26, 7:29 PM MDT	Severe Thunderstorm Warning	GGW	Garfield, McCone, Valley	61 min

Nearby

Severe Thunderstorm Warnings in Montana, 2002 Every 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.