Alert archive / Montana / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 2, NWS Missoula, MT

June 23, 2011Flathead County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Jun 23, 2011, 12:29 PM MDT for Flathead County, Montana. It was in force for 34 min. 2 reports 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
Jun 23, 2011, 12:29 PM MDT (18:29 UTC)
Expired
Jun 23, 2011, 1:03 PM MDT
In force
34 min
Issued by
NWS Missoula, MT
Area
Storm-based polygon

County Flathead County, MT

The radar

The Missoula radar (KMSX), 159 km from the middle of the area, began a volume at 18:32 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
Jun 23, 12:39 PM MDTHAIL 0.52 N Creston, MTDIME SIZED HAIL REPORTED BY SPOTTER.
Jun 23, 1:00 PM MDTHAIL 1.252 Nne Creston, MTSPOTTER REPORTED SOME SHINGLE DAMAGE AND DENTS IN COPPER ROOFING.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Spokane, WA (KOTX), launched 12:00Z, 6.5 hours before the alert went out and 223 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 2011-06-23Temperature 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 2011-06-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1871 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
17 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.

869 
WUUS55 KMSO 231829
SVRMSO
MTC029-231915-
/O.NEW.KMSO.SV.W.0002.110623T1829Z-110623T1915Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
1229 PM MDT THU JUN 23 2011

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL FLATHEAD COUNTY IN NORTHWEST MONTANA...

* UNTIL 115 PM MDT.

* AT 1222 PM MDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING HAIL UP TO ONE INCH IN DIAMETER.  THIS STORM
  WAS LOCATED NEAR KALISPELL...AND WAS MOVING NORTHEAST AT 50 MPH.

* LOCATIONS IMPACTED INCLUDE...CRESTON...EVERGREEN...KALISPELL...
  NYACK AND PINNACLE.

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 4856 11350 4856 11347 4855 11345 4846 11347
      4843 11341 4842 11334 4806 11419 4821 11435
      4859 11360 4859 11355
TIME...MOT...LOC 1829Z 234DEG 43KT 4818 11416

$$

DICKERSON
1 follow-up statement
444 
WWUS55 KMSO 231903
SVSMSO

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MISSOULA MT
103 PM MDT THU JUN 23 2011

MTC029-231911-
/O.CAN.KMSO.SV.W.0002.000000T0000Z-110623T1915Z/
FLATHEAD MT-
103 PM MDT THU JUN 23 2011

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL FLATHEAD COUNTY IS
CANCELLED...

THE THUNDERSTORM WHICH PROMPTED THE WARNING HAS WEAKENED AND IS NO 
LONGER CONSIDERED SEVERE. HEAVY RAIN WITH PEA SIZED HAIL ARE STILL 
POSSIBLE AS THIS STORM TRACKS NORTHEAST AT AROUND 40 MPH INTO 
GLACIER NATIONAL PARK OVER THE NEXT 45 MINUTES.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 800 PM MDT
THURSDAY EVENING FOR NORTHWESTERN MONTANA.

LAT...LON 4856 11350 4856 11347 4855 11345 4846 11347
      4843 11341 4842 11334 4806 11419 4821 11435
      4859 11360 4859 11355
TIME...MOT...LOC 1901Z 234DEG 43KT 4840 11369

$$

DICKERSON

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 23, 1:51 AM MDTSpecial Weather StatementMSOFlathead39 min
Jun 23, 11:17 AM MDTAreal Flood WarningMSODeer Lodge14 days
Jun 23, 11:49 AM MDTAreal Flood WarningMSOMissoula68 hr
Jun 23, 12:19 PM MDTSpecial Weather StatementMSOFlathead41 min
Jun 23, 1:34 PM MDTSevere Thunderstorm WarningMSOMissoula, Powell26 min

Nearby

Severe Thunderstorm Warnings in Montana, 2011Every severe thunderstorm warning in 2011

Sources

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