Alert archive / Montana / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 68, NWS Billings, MT

August 6, 2020Carter County, Montana

NWS Billings, MT issued this severe thunderstorm warning at Aug 6, 2020, 6:14 PM MDT for Carter County, Montana. It was in force for 76 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: Aug 6, 2020, 6:14 PM MDT (00:14 UTC)
Expired: Aug 6, 2020, 7:30 PM MDT
In force: 76 min
Issued by: NWS Billings, MT
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Carter County, MT

The radar

The Rapid City radar (KUDX), 205 km from the middle of the area, began a volume at 00:18 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

Glasgow Intl Airport, MT (KGGW), launched 00:00Z, 0.2 hours before the alert went out and 339 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: 912 J/kg
Mixed-layer CIN: -97 J/kg
Mixed-layer LCL: 2900 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 42 m²/s²
0-3 km storm-relative helicity: 197 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.8

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 Billings, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 6, 3:11 PM MDT, 3 hours 3 minutes earlier.

Area forecast discussion, Aug 6, 3:11 PM MDT, 3 hours 3 minutes before

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In the hours before

Special weather statement, Aug 6, 1:09 PM MDT, 5 hours 5 minutes before

Special Weather Statement
National Weather Service Billings MT
109 PM MDT Thu Aug 6 2020

MTZ040-064-065-067-068-061945-
Paradise Valley MT-Northern Park MT-Absaroka/Beartooth Mountains MT-
Crazy Mountains MT-Livingston Area MT-
109 PM MDT Thu Aug 6 2020

...SIGNIFICANT WEATHER ADVISORY...

At 105 PM MDT, Doppler radar was tracking a a cluster of strong
thunderstorm near Livingston, moving northeast at 25 mph.

Wind gusts to 50 mph are possible with this activity, small hail up
to half inch hail is also possible.

Locations impacted include...
Livingston, Clyde Park, Pine Creek, Springdale, Wilsall and Emigrant.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
office in Billings.

&&

LAT...LON 4535 11094 4535 11092 4553 11090 4553 11086
      4559 11085 4559 11080 4601 11078 4609 11020
      4591 11021 4589 11028 4586 11030 4579 11029
      4578 11022 4536 11023 4533 11095
TIME...MOT...LOC 1905Z 222DEG 21KT 4571 11066

Gilstad

Special weather statement, Aug 6, 2:49 PM MDT, 3 hours 25 minutes before

Special Weather Statement
National Weather Service Billings MT
249 PM MDT Thu Aug 6 2020

MTZ034-056-066-141-170-062130-
Beartooth Foothills MT-Red Lodge Foothills MT-Northern Carbon MT-
Northern Stillwater MT-Northern Sweet Grass MT-
249 PM MDT Thu Aug 6 2020

...SIGNIFICANT WEATHER ADVISORY...

At 248 PM MDT, Doppler radar was tracking a strong thunderstorm 17
miles north of Absarokee, or 17 miles northwest of Columbus, moving
east at 30 mph.

Dime size hail and winds in excess of 30 mph are possible with this
storm.

Locations impacted include...
Columbus, Joliet, Fromberg, Absarokee, Reed Point, Edgar, Fishtail,
Boyd, Molt, Cooney Reservoir State Park, Park City, Rockvale and
Halfbreed Lake Wildlife.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4541 10960 4585 10976 4597 10892 4596 10892
      4596 10890 4569 10890 4568 10888 4566 10888
      4565 10887 4564 10887 4564 10885 4538 10884
TIME...MOT...LOC 2048Z 259DEG 32KT 4576 10957

Gilstad

Local storm report, Aug 6, 3:44 PM MDT, 2 hours 30 minutes before

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Special weather statement, Aug 6, 3:50 PM MDT, 2 hours 24 minutes before

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Special weather statement, Aug 6, 4:32 PM MDT, 1 hour 42 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 6, 6:03 PM MDT	Special Weather Statement	BYZ	Carter	42 min
Aug 6, 6:21 PM MDT	Special Weather Statement	BYZ	Treasure	39 min
Aug 6, 7:27 PM MDT	Special Weather Statement	BYZ	Carter	48 min

Nearby

Severe Thunderstorm Warnings in Montana, 2020 Every severe thunderstorm warning in 2020

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.