Alert archive / Montana / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 90, NWS Great Falls, MT

July 23, 2008Pondera County, Teton County, Montana

NWS Great Falls, MT issued this severe thunderstorm warning at Jul 23, 2008, 10:19 PM MDT for Pondera County, Teton County, Montana. It was in force for 41 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, 2008, 10:19 PM MDT (04:19 UTC)
Expired
Jul 23, 2008, 11:00 PM MDT
In force
41 min
Issued by
NWS Great Falls, MT
Area
Storm-based polygon

Counties Pondera County, MT, Teton County, MT

The radar

The Great Falls radar (KTFX), 90 km from the middle of the area, began a volume at 04:21 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.

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 4.3 hours before the alert went out and 138 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, Great_falls, MT at 00:00Z on 2008-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Great_falls, MT at 00:00Z on 2008-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 46 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
2742 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
134 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

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 Great Falls, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 23, 9:46 PM MDT, 33 minutes earlier.

Area forecast discussion, Jul 23, 9:46 PM MDT, 33 minutes before
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Hazardous weather outlook, Jul 23, 5:23 AM MDT, 16 hours 56 minutes before
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In the hours before

Local storm report, Jul 23, 10:02 PM MDT, 17 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1002 PM MDT WED JUL 23 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0727 PM     TSTM WND GST     W FLOWEREE              47.73N 111.03W
07/23/2008  E70 MPH          CHOUTEAU           MT   TRAINED SPOTTER

            WIND GUST OF 70 MPH ESTIMATED DUE TO WIND BREAKING
            BRANCHES UP TO 2 INCHES IN DIAMETER. HEAVY RAIN ALSO
            FELL...AT LEAST 0.40 INCHES AS IT WAS WIND BLOWN. WATER
            RUNNING DOWN THE ROADS BUT NO FLOODING. RAIN AND WIND
            OCCURRED FROM APPROXIMATELY 707 PM MDT UNTIL 727 PM MDT.

&&

COULSTON
Local storm report, Jul 23, 10:06 PM MDT, 13 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1006 PM MDT WED JUL 23 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0616 PM     HEAVY RAIN       CONRAD                  48.17N 111.95W
07/23/2008  M0.20 INCH       PONDERA            MT   TRAINED SPOTTER

            SPOTTER REPORTED 10 TO 15 MINUTES OF HEAVY RAIN THAT JUST
            ENDED AND TOTALED 0.20 INCHES. THERE IS WATER RUNNING
            DOWN THE ROADS CAUSING MINOR STREET FLOODING.

&&

COULSTON

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 7:59 PM MDTSevere Thunderstorm WarningTFXChouteau39 min
Jul 23, 8:54 PM MDTSevere Thunderstorm WarningTFXCascade, Lewis and Clark51 min
Jul 23, 9:36 PM MDTSevere Thunderstorm WarningTFXCascade, Lewis and Clark, Meagher54 min
Jul 23, 10:25 PM MDTSevere Thunderstorm WarningTFXCascade, Judith Basin, Meagher50 min
Jul 23, 10:32 PM MDTTornado WarningTFXPondera28 min
Jul 23, 10:55 PM MDTSevere Thunderstorm WarningTFXPondera, Toole50 min
Jul 23, 11:45 PM MDTSevere Thunderstorm WarningTFXToole30 min

Nearby

Severe Thunderstorm Warnings in Montana, 2008Every severe thunderstorm warning in 2008

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; radar from the NEXRAD Level II archive.