Alert archive / Montana / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 49, NWS Missoula, MT

July 20, 2012Flathead County, Lake County, Lincoln County, Montana

NWS Missoula, MT issued this severe thunderstorm warning at Jul 20, 2012, 6:13 PM MDT for Flathead County, Lake County, Lincoln County, Montana. It was in force for 62 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 20, 2012, 6:13 PM MDT (00:13 UTC)
Expired
Jul 20, 2012, 7:15 PM MDT
In force
62 min
Issued by
NWS Missoula, MT
Area
Storm-based polygon

Counties Flathead County, MT, Lake County, MT, Lincoln County, MT

The radar

The Missoula radar (KMSX), 190 km from the middle of the area, began a volume at 00:15 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
Jul 20, 6:13 PM MDTTSTM WND GST 70Eureka, MT

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

The watch it was issued in

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

IssuedProductOfficeLasted
Jul 20, 12:38 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Spokane, WA (KOTX), launched 00:00Z, 0.2 hours before the alert went out and 170 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 2012-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 46 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 2012-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
46 J/kg
Mixed-layer CIN
-200 J/kg
Mixed-layer LCL
1692 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
47 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.

840 
WUUS55 KMSO 210013
SVRMSO
MTC029-047-053-210115-
/O.NEW.KMSO.SV.W.0049.120721T0013Z-120721T0115Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
613 PM MDT FRI JUL 20 2012

THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A

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

* UNTIL 715 PM MDT.

* AT 606 PM MDT...LAW ENFORCEMENT REPORTED A LINE OF SEVERE
  THUNDERSTORMS CAPABLE OF PRODUCING DESTRUCTIVE WINDS IN EXCESS OF
  70 MPH.  THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 11
  MILES NORTHWEST OF EUREKA TO 15 MILES SOUTHEAST OF EUREKA TO 17
  MILES SOUTHWEST OF KALISPELL...OR ALONG A LINE EXTENDING FROM 45
  MILES NORTH OF LIBBY TO 38 MILES NORTHEAST OF LIBBY TO 17 MILES
  SOUTHWEST OF KALISPELL...AND WERE MOVING NORTHEAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...APGAR...COLUMBIA FALLS...CORAM...
  CRESTON...EUREKA...EVERGREEN...FORTINE...HUNGRY HORSE...
  KALISPELL...KILA...LA SALLE...LUPFER...MARION...MARTIN CITY...
  OLNEY...POLEBRIDGE...RADNOR...REXFORD...SOMERS...STRYKER...
  TRAILCREEK...TREGO...WEST GLACIER AND WHITEFISH.

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.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM MDT FRIDAY
EVENING FOR NORTH CENTRAL IDAHO AND NORTHWESTERN MONTANA.

&&

LAT...LON 4901 11413 4826 11373 4789 11462 4863 11509
      4900 11545 4902 11538
TIME...MOT...LOC 0013Z 235DEG 31KT 4903 11514 4873 11480
          4803 11443

$$
KITSMILLER
1 follow-up statement
600 
WWUS55 KMSO 210107
SVSMSO

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MISSOULA MT
707 PM MDT FRI JUL 20 2012

MTC029-047-053-210117-
/O.EXP.KMSO.SV.W.0049.000000T0000Z-120721T0115Z/
LINCOLN MT-LAKE MT-FLATHEAD MT-
707 PM MDT FRI JUL 20 2012

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN FLATHEAD...
NORTHWESTERN LAKE AND NORTHEASTERN LINCOLN COUNTIES EXPIRES AT 715 PM
MDT...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM MDT FRIDAY
EVENING FOR NORTHWESTERN MONTANA.

LAT...LON 4901 11413 4826 11373 4789 11462 4863 11509
      4900 11545 4902 11538
TIME...MOT...LOC 0107Z 235DEG 31KT 4930 11456 4899 11422
          4829 11386

$$
KITSMILLER

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.