Alert archive / Montana / Special Weather Statements in 2017

Special Weather Statement, NWS Great Falls, MT

August 10, 2017Teton County, Montana

NWS Great Falls, MT issued this special weather statement at Aug 10, 2017, 9:10 PM MDT for Teton County, Montana. It was in force for 50 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 10, 2017, 9:10 PM MDT (03:10 UTC)
Expired: Aug 10, 2017, 10:00 PM MDT
In force: 50 min
Issued by: NWS Great Falls, MT

County Teton County, MT

The radar

The Missoula radar (KMSX), 119 km from the middle of the area, began a volume at 03:13 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, 3.2 hours before the alert went out and 183 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 3178 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 17 m²/s²
0-3 km storm-relative helicity: 6 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

393 
WWUS85 KTFX 110310
SPSTFX

Special Weather Statement
National Weather Service Great Falls MT
910 PM MDT THU AUG 10 2017
 
MTZ009-014-048-110400-
Southern Rocky Mountain Front MT-Northern Rocky Mountain Front MT-
Central and Southern Lewis and Clark MT-
910 PM MDT THU AUG 10 2017

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN LEWIS AND CLARK...
WEST CENTRAL PONDERA AND WESTERN TETON COUNTIES UNTIL 1000 PM MDT...

At 908 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from 13 miles southwest of Heart Butte to 26 miles
east of Swan Lake. Movement was southeast at 35 mph.

Pea size hail and winds approaching 40 mph will be possible with 
these storms.

Locations impacted include...
Pishkun Reservoir and Bynum. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent lightning is occurring with these storms. Lightning can 
strike 10 miles away from a thunderstorm. Seek a safe shelter inside 
a building or vehicle.

Persons in campgrounds should consider seeking sturdy shelter until
these storms pass.

&&

LAT...LON 4778 11307 4792 11309 4798 11288 4801 11289
      4804 11295 4806 11294 4808 11299 4812 11299
      4812 11305 4814 11308 4823 11300 4799 11212
      4723 11292 4738 11306 4748 11306 4750 11312
      4772 11317
TIME...MOT...LOC 0308Z 314DEG 33KT 4813 11300 4779 11332 

$$

Moldan

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 10, 10:02 PM MDT	Special Weather Statement	TFX	Teton	28 min
Aug 10, 10:31 PM MDT	Special Weather Statement	TFX	Lewis and Clark, Teton	44 min
Aug 10, 11:20 PM MDT	Special Weather Statement	TFX	Cascade	40 min

Nearby

Special Weather Statements in Montana, 2017 Every special weather statement in 2017

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.