Alert archive / Montana / Severe Thunderstorm Watches in 2008

Severe Thunderstorm Watch 754

July 26, 200811 counties in Montana

The Storm Prediction Center issued this severe thunderstorm watch at Jul 26, 2008, 2:41 PM MDT for 11 counties in Montana. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Jul 26, 2008, 2:41 PM MDT (20:41 UTC)
Expired
Jul 26, 2008, 10:00 PM MDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
3 in
Strongest gust expected
60 kt

Counties Blaine County, MT, Chouteau County, MT, Fergus County, MT, Garfield County, MT, Hill County, MT, Judith Basin County, MT, McCone County, MT, Petroleum County, MT, Phillips County, MT, Prairie County, MT, Valley County, MT

The radar

The Glasgow radar (KGGW), 147 km from the middle of the area, began a volume at 20:42 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
10%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
40%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
40%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

15 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jul 26, 3:17 PM MDTSevere Thunderstorm WarningTFXBlaine58 min
Jul 26, 3:49 PM MDTSevere Thunderstorm WarningTFXFergus26 min
Jul 26, 3:57 PM MDTSevere Thunderstorm WarningGGWPetroleum40 min
Jul 26, 4:14 PM MDTSevere Thunderstorm WarningTFXBlaine31 min
Jul 26, 4:34 PM MDTSevere Thunderstorm WarningGGWPhillips56 min
Jul 26, 4:39 PM MDTSevere Thunderstorm WarningGGWPhillips66 min
Jul 26, 5:27 PM MDTSevere Thunderstorm WarningGGWPhillips63 min
Jul 26, 5:57 PM MDTTornado WarningGGWPhillips34 min
Jul 26, 6:25 PM MDTSevere Thunderstorm WarningGGWGarfield, Petroleum37 min
Jul 26, 6:29 PM MDTSevere Thunderstorm WarningGGWGarfield, Phillips, Valley61 min
Jul 26, 6:41 PM MDTSevere Thunderstorm WarningGGWRoosevelt, Valley64 min
Jul 26, 8:29 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Richland61 min
Jul 26, 8:57 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Prairie63 min
Jul 26, 9:32 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Richland58 min
Jul 26, 9:53 PM MDTSevere Thunderstorm WarningGGWDawson, McCone, Prairie67 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Glasgow Intl Airport, MT (KGGW), launched 12:00Z, 8.7 hours before the alert went out and 149 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, Glasgow Intl Airport, MT at 12:00Z on 2008-07-26Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Glasgow Intl Airport, MT at 12:00Z on 2008-07-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 327 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
2124 m above ground
0-6 km bulk shear
56 kt
0-1 km storm-relative helicity
327 m²/s²
0-3 km storm-relative helicity
305 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 26, 1:44 PM MDTMesoscale DiscussionSPCBig Horn, Carter, Custer, Dawson, Fallon, Fergus and 10 more61 min
Jul 26, 5:48 PM MDTMesoscale DiscussionSPCCuster, Dawson, Fallon, Fergus, Garfield, McCone and 7 more117 min

Nearby

Severe Thunderstorm Watches in Montana, 2008Every severe thunderstorm watch 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.