Alert archive / Montana / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 24, NWS Missoula, MT

July 23, 2002Lake County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Jul 23, 2002, 3:42 PM MDT for Lake County, Montana. It was in force for 33 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
Jul 23, 2002, 3:42 PM MDT (21:42 UTC)
Expired
Jul 23, 2002, 4:15 PM MDT
In force
33 min
Issued by
NWS Missoula, MT
Area
Whole counties

County Lake County, MT

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 23, 2:30 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Spokane, WA (KOTX), launched 12:00Z, 9.7 hours before the alert went out and 173 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, Spokane, WA at 12:00Z on 2002-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Spokane, WA at 12:00Z on 2002-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -19 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2677 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-19 m²/s²
0-3 km storm-relative helicity
26 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.

658 
WUUS55 KMSO 232142
SVRMSO
MTC047-232215-

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

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN LAKE COUNTY IN NORTHWEST MONTANA

* UNTIL 415 PM MDT

* AT 341 PM MDT...RADAR INDICATED A SEVERE THUNDERSTORM OVER ARLEE...
  OR 22 MILES NORTH OF MISSOULA...MOVING EAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL REMAIN OVER REMOTE AREAS.

THIS STORM PRODUCED GOLF BALL SIZE HAIL IN ARLEE AT 340 PM MDT.

DAMAGING WINDS IN EXCESS OF 55 MPH ARE LIKELY WITH THIS SEVERE 
THUNDERSTORM. LARGE HAIL...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.

&

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, 1 hour 22 minutes earlier.

Area forecast discussion, Jul 23, 2:20 PM MDT, 1 hour 22 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

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; the sounding from the Mesonet's radiosonde archive.