Alert archive / Montana / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 22, NWS Missoula, MT

June 23, 2012Lake County, Missoula County, Sanders County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Jun 23, 2012, 7:14 PM MDT for Lake County, Missoula County, Sanders County, Montana. It was in force for 31 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, 2012, 7:14 PM MDT (01:14 UTC)
Expired
Jun 23, 2012, 7:45 PM MDT
In force
31 min
Issued by
NWS Missoula, MT
Area
Storm-based polygon

Counties Lake County, MT, Missoula County, MT, Sanders County, MT

The radar

The Missoula radar (KMSX), 15 km from the middle of the area, began a volume at 01:17 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, 7:14 PM MDTTSTM WND GST 796 Nw Missoula, MTDOWNED TREE DAMAGED NEARBY BUILDING. QUARTER SIZE HAIL ALSO.
Jun 23, 7:16 PM MDTHAIL 16 Nw Missoula, MT

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 00:00Z, 1.2 hours before the alert went out and 181 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 2012-06-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 106 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 2012-06-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -144 square meters per square second.1939587897117Sfc1 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
106 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
1228 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
-144 m²/s²
0-3 km storm-relative helicity
-99 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.3

Open this sounding in Storm Lab

The text

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

505 
WUUS55 KMSO 240114
SVRMSO
MTC047-063-089-240145-
/O.NEW.KMSO.SV.W.0022.120624T0114Z-120624T0145Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
714 PM MDT SAT JUN 23 2012

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN SANDERS COUNTY IN NORTHWEST MONTANA...
  SOUTHERN LAKE COUNTY IN NORTHWEST MONTANA...
  CENTRAL MISSOULA COUNTY IN WEST CENTRAL MONTANA...

* UNTIL 745 PM MDT.

* AT 711 PM MDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
  CAPABLE OF PRODUCING DESTRUCTIVE WINDS IN EXCESS OF 70 MPH.  THIS
  STORM WAS LOCATED 6 MILES SOUTHEAST OF FRENCHTOWN...OR ABOUT 9
  MILES NORTHWEST OF MISSOULA...AND WAS MOVING NORTH AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...ARLEE...EVARO...FRENCHTOWN AND
  RAVALLI.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DAMAGING WINDS ARE LIKELY WITH THIS SEVERE THUNDERSTORM. LARGE HAIL
IS 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 4729 11426 4726 11393 4685 11404 4687 11430
TIME...MOT...LOC 0114Z 187DEG 25KT 4696 11415

$$
1 follow-up statement
714 
WWUS55 KMSO 240126
SVSMSO

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MISSOULA MT
726 PM MDT SAT JUN 23 2012

MTC047-063-089-240145-
/O.CON.KMSO.SV.W.0022.000000T0000Z-120624T0145Z/
MISSOULA MT-LAKE MT-SANDERS MT-
726 PM MDT SAT JUN 23 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM MDT
FOR SOUTHEASTERN SANDERS...SOUTHERN LAKE AND CENTRAL MISSOULA
COUNTIES...

* AT 718 PM MDT...TRAINED WEATHER SPOTTERS REPORTED A SEVERE   
THUNDERSTORM PRODUCING DESTRUCTIVE WINDS OF 79 MPH.  THIS STORM WAS 
LOCATED NEAR EVARO...OR ABOUT 11 MILES NORTHWEST OF MISSOULA...AND 
WAS MOVING NORTH AT 30 MPH.

LAT...LON 4729 11426 4726 11393 4685 11404 4687 11430
TIME...MOT...LOC 0126Z 187DEG 25KT 4704 11413

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 23, 6:18 PM MDTSpecial Weather StatementMSOMissoula27 min
Jun 23, 6:23 PM MDTSpecial Weather StatementMSOFlathead52 min
Jun 23, 6:47 PM MDTSpecial Weather StatementMSOMissoula43 min
Jun 23, 7:18 PM MDTAreal Flood AdvisoryMSOMissoula94 min
Jun 23, 7:39 PM MDTSevere Thunderstorm WarningMSOLake, Missoula51 min
Jun 23, 7:52 PM MDTSevere Thunderstorm WarningMSOFlathead, Lake, Missoula, Powell38 min
Jun 23, 8:21 PM MDTSevere Thunderstorm WarningMSOFlathead, Missoula, Powell39 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.