Alert archive / Montana / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 56, NWS Missoula, MT

July 27, 2012Flathead County, Lake County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Jul 27, 2012, 11:11 PM MDT for Flathead County, Lake County, Montana. It was in force for 38 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 27, 2012, 11:11 PM MDT (05:11 UTC)
Expired
Jul 27, 2012, 11:49 PM MDT
In force
38 min
Issued by
NWS Missoula, MT
Area
Storm-based polygon

Counties Flathead County, MT, Lake County, MT

The nearest sounding before it

Spokane, WA (KOTX), launched 00:00Z, 5.2 hours before the alert went out and 225 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 00:00Z on 2012-07-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 328 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2012-07-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 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
328 J/kg
Mixed-layer CIN
-82 J/kg
Mixed-layer LCL
2524 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
32 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

800 
WUUS55 KMSO 280511
SVRMSO
MTC029-047-280615-
/O.NEW.KMSO.SV.W.0056.120728T0511Z-120728T0615Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
1111 PM MDT FRI JUL 27 2012

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  FLATHEAD COUNTY IN NORTHWEST MONTANA...
  NORTHEASTERN LAKE COUNTY IN NORTHWEST MONTANA...

* UNTIL 1215 AM MDT.

* AT 1104 PM MDT...TRAINED WEATHER SPOTTERS REPORTED A LINE OF SEVERE
  THUNDERSTORMS CAPABLE OF PRODUCING HAIL UP TO ONE INCH IN DIAMETER.
   THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM BIGFORK TO
  18 MILES SOUTH OF SWAN LAKE...OR ALONG A LINE EXTENDING FROM 12
  MILES SOUTHEAST OF KALISPELL TO 19 MILES EAST OF POLSON...AND WERE
  MOVING NORTHEAST AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...APGAR...BIGFORK...BLACKTAIL...COLUMBIA
  FALLS...CORAM...CRESTON...ESSEX...EVERGREEN...FINLEY POINT...HUNGRY
  HORSE...KALISPELL...LA SALLE...LAKE MCDONALD...LAKESIDE...LOGAN
  PASS...MARTIN CITY...NYACK...PINNACLE...ROLLINS...SALMON PRAIRIE...
  SOMERS...SWAN LAKE...WEST GLACIER...WHITEFISH AND WOODS BAY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

LARGE HAIL IS LIKELY WITH THIS SEVERE THUNDERSTORM. DAMAGING WINDS
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 4874 11370 4862 11374 4855 11345 4846 11347
      4842 11334 4834 11337 4825 11322 4818 11322
      4813 11300 4802 11288 4793 11293 4791 11308
      4778 11305 4773 11315 4761 11313 4760 11391
      4745 11391 4743 11402 4843 11456 4878 11376
TIME...MOT...LOC 0510Z 236DEG 24KT 4810 11408 4770 11370

$$
1 follow-up statement
685 
WWUS55 KMSO 280549
SVSMSO

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MISSOULA MT
1149 PM MDT FRI JUL 27 2012

MTC029-047-280559-
/O.CAN.KMSO.SV.W.0056.000000T0000Z-120728T0615Z/
LAKE MT-FLATHEAD MT-
1149 PM MDT FRI JUL 27 2012

...THE SEVERE THUNDERSTORM WARNING FOR FLATHEAD AND NORTHEASTERN LAKE
COUNTIES IS CANCELLED...

THE STORMS HAVE WEAKENED BELOW SEVERE LIMITS HOWEVER MAY STILL 
PRODUCE SMALL HAIL AND GUSTY WINDS.

LAT...LON 4874 11370 4862 11374 4855 11345 4846 11347
      4842 11334 4834 11337 4825 11322 4818 11322
      4813 11300 4802 11288 4793 11293 4791 11308
      4778 11305 4773 11315 4761 11313 4760 11391
      4745 11391 4743 11402 4843 11456 4878 11376
TIME...MOT...LOC 0549Z 236DEG 24KT 4825 11376 4784 11338

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 27, 8:27 PM MDTSpecial Weather StatementMSOLake63 min
Jul 27, 9:24 PM MDTSpecial Weather StatementMSOMissoula66 min
Jul 27, 9:57 PM MDTSpecial Weather StatementMSOFlathead63 min
Jul 27, 10:05 PM MDTSpecial Weather StatementMSOFlathead70 min
Jul 27, 10:27 PM MDTSevere Thunderstorm WarningMSOFlathead38 min
Jul 27, 10:47 PM MDTSpecial Weather StatementMSOFlathead58 min
Jul 28, 12:44 AM MDTSpecial Weather StatementMSOFlathead61 min

Nearby

Severe Thunderstorm Warnings in Montana, 2012Every severe thunderstorm warning in 2012

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.