Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 25, NWS Missoula, MT

July 23, 2002Ravalli County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Jul 23, 2002, 8:13 PM MDT for Ravalli County, Montana. It was in force for 32 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jul 23, 2002, 8:13 PM MDT (02:13 UTC)
Expired: Jul 23, 2002, 8:45 PM MDT
In force: 32 min
Issued by: NWS Missoula, MT
Area: Counties, with a storm outline in the text

County Ravalli County, MT

What was reported inside it

Time	Report	Where	Remark
Jul 23, 8:20 PM MDT	Hail 1	Stevensville, 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Spokane, WA (KOTX), launched 00:00Z, 2.2 hours before the alert went out and 228 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 3410 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: -23 m²/s²
0-3 km storm-relative helicity: -21 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

053 
WUUS55 KMSO 240213
SVRMSO
MTC081-240245-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
812 PM MDT TUE JUL 23 2002

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN RAVALLI COUNTY IN WEST CENTRAL MONTANA

* UNTIL 845 PM MDT

* AT 812 PM MDT...SPOTTERS REPORTED A SEVERE THUNDERSTORM 8 MILES
  EAST OF BELL CROSSING...OR 16 MILES NORTHEAST OF               
  HAMILTON...MOVING NORTHEAST AT 20 MPH. 1 INCH HAIL WAS REPORTED 
  WITH THIS STORM.

* THE SEVERE THUNDERSTORM WILL REMAIN OVER REMOTE AREAS.

LARGE HAIL IS LIKELY WITH THIS SEVERE THUNDERSTORM. DAMAGING WINDS IN
EXCESS OF 55 MPH ARE POSSIBLE...ALONG WITH FREQUENT LIGHTNING AND
HEAVY RAIN. FOR YOUR PROTECTION...GO INDOORS AND STAY AWAY FROM
WINDOWS. IF YOU ARE CAUGHT OUTSIDE...MOVE TO A WELL PROTECTED AREA.

&

LAT...LON 4644 11415 4631 11396 4641 11387 4659 11400

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 Missoula, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 23, 2:20 PM MDT, 5 hours 53 minutes earlier.

Area forecast discussion, Jul 23, 2:20 PM MDT, 5 hours 53 minutes before

WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
220 PM MDT TUE JUL 23 2002

.SHORT TERM...CONVECTION BEGINNING TO DEVELOP ACROSS THE SOUTH THIS
AFTERNOON. STABILITY INDICES SHOW AIR MASS WILL BE PLENTY UNSTABLE
FOR SCATTERED THUNDERSTORM COVERAGE BUT LOW QPF THIS EVENING...WITH
EVEN SOME ISOLATED ACTIVITY OVERNIGHT. WEAK LOW SYSTEM WILL REMAIN
OFF THE WEST COAST TONIGHT...THEN BEGIN TO FILL AS IT MOVES NORTH. AS
A RESULT THE RIDGE SHARPENS OVER THE NORTHERN ROCKIES AND DRYING
EXPECTED REDUCING POPS FOR WED/WED NIGHT. WILL BUMP TEMPS UP FOR WED
IN RESPONSE TO WARMING AIR MASS UNDER RIDGE. MESOETA SUGGESTS A WEAK
DISTURBANCE PUSHING INTO THE RIDGE WED NIGHT FOR SLIGHT CHANCE POPS
ACROSS THE MID-SECTION OF CWA.

THU...PATTERN DE-AMPLIFIES WITH A LOW LEVEL CONV/UPPER LEVEL DIV
COUPLET DEVELOPING ACROSS THE SOUTH LATER. THE AIR MASS CONTINUES
TO BE QUITE UNSTABLE DURING THE HEATING OF THE DAY AND MOISTURE IS
THE MAIN QUESTION MARK...WITH POSSIBLY ANOTHER DRY LIGHTNING EVENT.
CONVECTION WILL CARRY INTO THE EVENING HOURS ACROSS THE SOUTH.

FRI...A DRY WEST-NORTHWESTERLY FLOW EXPECTED WITH COOLER TEMPS. MSJ

.LONG TERM...SATURDAY AND SUNDAY THE TROUGH CROSSES ACROSS THE AREA.
WITH A DRY NORTHWEST FLOW ALOFT. THE CWA SHOULD JUST SEE SOME CLOUDS
FROM THIS.  MONDAY AND TUESDAY THE FLOW GOES WESTERLY WITH A
FLATTENED RIDGE POKING INTO THE AREA. TEMPERATURES WILL RISE
SLIGHTLY THROUGH THE PERIOD REMAINING NEAR NORMAL THROUGHOUT THE
FORECAST. GILCHRIST

.MSO...RFW FOR DRY LIGHTNING TONIGHT IN ZONES 104 105 106 107.

...7-DAY SPOT TEMPS AND POPS...
LIB BBU 055/094 055/090 054/087 35100010
     BBUU 052/084 052/085 053/086 053/087 3300000000
FCA BBB 054/089 052/085 052/083 35100010
     BBUU 050/078 050/080 051/081 051/082 3300000000
POL BBB 062/087 061/084 056/082 35100000
     BBUU 053/077 053/079 053/080 053/081 3300000000
MSO BBB 058/091 058/088 055/086 35101100
     BBUU 052/082 050/082 050/083 050/083 3300000000
HMM BBB 059/090 058/087 054/085 35201100
     BBUU 051/080 048/080 048/082 049/082 3300000000
BTM BBB 053/087 051/085 050/083 35200210
     BBUU 047/078 045/078 046/079 048/080 3300000000
ORO BBU 063/097 062/093 064/091 35100100
     BBUU 060/086 059/088 059/090 059/090 3300000000
GRV BBB 059/092 059/088 056/086 35100100
     BBUU 053/083 051/084 051/085 052/086 3300000000
SMN BBB 056/092 055/087 054/085 35200210
     BBUU 052/082 051/083 050/084 051/085 3300000000

In the hours before

Local storm report, Jul 23, 8:05 PM MDT, 8 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
805 PM MDT TUE JUL 23 2002

TIME(MDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION......

340 PM     ARLEE                     MT   1.5 INCH HAIL
07/23/02   LAKE

341 PM     ARLEE                     MT   1.5 INCH HAIL
07/23/02   LAKE

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.