Alert archive / Wyoming / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 334, NWS Cheyenne, WY

August 15, 2019Goshen County, Platte County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Aug 15, 2019, 10:44 PM MDT for Goshen County, Platte County, Wyoming. It was in force for 31 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 15, 2019, 10:44 PM MDT (04:44 UTC)
Expired: Aug 15, 2019, 11:15 PM MDT
In force: 31 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.5 in
Wind: 60.0 mph

Counties Goshen County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 107 km from the middle of the area, began a volume at 04:46 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

Rapid City, SD (KUNR), launched 00:00Z, 4.7 hours before the alert went out and 261 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: 2 J/kg
Mixed-layer CIN: -121 J/kg
Mixed-layer LCL: 1848 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: 8 m²/s²
0-3 km storm-relative helicity: 151 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.3

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 Cheyenne, WY wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 15, 10:09 PM MDT, 35 minutes earlier.

Area forecast discussion, Aug 15, 10:09 PM MDT, 35 minutes before

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Hazardous weather outlook, Aug 15, 10:43 AM MDT, 12 hours 1 minute before

Hazardous Weather Outlook
National Weather Service Cheyenne WY
1043 AM MDT Thu Aug 15 2019

NEZ002-003-019-021-095-096-WYZ101-102-107-108-161000-
Dawes-Box Butte-Scotts Bluff-Morrill-North Sioux-South Sioux-
Converse County Lower Elevations-Niobrara County-
East Platte County-Goshen County-
1043 AM MDT Thu Aug 15 2019

This hazardous weather outlook is for portions of western
Nebraska...east central Wyoming and southeast Wyoming.

.DAY ONE...TODAY AND TONIGHT

Isolated thunderstorms will be possible this afternoon with a few
strong storms possible. A somewhat greater threat for scattered
strong to severe storms is expected later tonight with large hail
the main threat.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

Widely scattered showers and storms are expected mainly on Friday,
with a few of the storms possibly becoming severe, mainly over the
Nebraska Panhandle.

.Spotter information statement...

Spotter activation is not expected at this time.

NEZ020-054-055-WYZ103>106-109>119-161000-
Banner-Kimball-Cheyenne-North Laramie Range-
Ferris/Seminoe/Shirley Mountains-Shirley Basin-
Central Laramie Range and Southwest Platte County-
Central Carbon County-North Snowy Range Foothills-
Southwest Carbon County-Sierra Madre Range-
Upper North Platte River Basin-Snowy Range-Laramie Valley-
South Laramie Range-South Laramie Range Foothills-
Central Laramie County-East Laramie County-
1043 AM MDT Thu Aug 15 2019

This hazardous weather outlook is for portions of western
Nebraska...south central Wyoming and southeast Wyoming.

.DAY ONE...TODAY AND TONIGHT

Isolated showers and thunderstorms are possible into this evening
but the severe threat is low.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

The probability for widespread hazardous weather is low.

.Spotter information statement...

Spotter activation will not be needed.

In the hours before

Local storm report, Aug 15, 5:21 PM MDT, 5 hours 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
521 PM MDT THU AUG 15 2019

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

0500 PM     HAIL             DALTON                  41.41N 102.97W
08/15/2019  M1.00 INCH       CHEYENNE           NE   EMERGENCY MNGR

&&

WILLS

Special weather statement, Aug 15, 5:23 PM MDT, 5 hours 21 minutes before

Special Weather Statement
National Weather Service Cheyenne WY
523 PM MDT Thu Aug 15 2019

NEZ054-160000-
Kimball NE-
523 PM MDT Thu Aug 15 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN KIMBALL COUNTY UNTIL
600 PM MDT...

At 523 PM MDT, Doppler radar was tracking a strong thunderstorm 11
miles south of Kimball Airport, or 14 miles south of Kimball, moving
east at 25 mph.

Penny size hail and winds in excess of 40 mph will be possible with
this storm.

This storm will remain over mainly rural areas of southeastern
Kimball County.

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 4101 10373 4108 10371 4107 10338 4100 10339
      4100 10372
TIME...MOT...LOC 2323Z 280DEG 23KT 4102 10362

Brothers

Local storm report, Aug 15, 5:36 PM MDT, 5 hours 8 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
536 PM MDT THU AUG 15 2019

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

0532 PM     HAIL             10 NE SIDNEY            41.24N 102.83W
08/15/2019  M1.00 INCH       CHEYENNE           NE   TRAINED SPOTTER

            GROUND PARTIALLY COVERED WITH HAIL

&&

WILLS

Special weather statement, Aug 15, 8:36 PM MDT, 2 hours 8 minutes before

Special Weather Statement
National Weather Service Cheyenne WY
836 PM MDT Thu Aug 15 2019

WYZ101-160300-
Converse County Lower Elevations WY-
836 PM MDT Thu Aug 15 2019

...SPECIAL WEATHER STATEMENT...

At 836 PM MDT, Doppler radar was tracking a strong thunderstorm 11
miles east of Teapot Rock, or 29 miles northeast of Casper, moving
east at 45 mph.

Half inch hail and winds in excess of 30 mph will be possible with
this storm.

This storm will remain over mainly rural areas of northwestern
Converse County.

LAT...LON 4325 10555 4299 10566 4310 10607 4331 10607
TIME...MOT...LOC 0236Z 282DEG 43KT 4322 10608

Brothers

Local storm report, Aug 15, 10:41 PM MDT, 3 minutes before

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The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 15, 8:36 PM MDT	Special Weather Statement	CYS	Converse	24 min
Aug 15, 8:50 PM MDT	Severe Thunderstorm Warning	CYS	Converse	40 min
Aug 15, 9:21 PM MDT	Red Flag Warning	CYS		23 hr
Aug 15, 9:29 PM MDT	Severe Thunderstorm Warning	CYS	Converse	76 min
Aug 15, 10:03 PM MDT	Severe Thunderstorm Warning	CYS	Converse	42 min
Aug 15, 10:24 PM MDT	Severe Thunderstorm Warning	CYS	Converse, Niobrara	51 min
Aug 15, 10:49 PM MDT	Special Weather Statement	CYS	Converse	26 min
Aug 15, 10:59 PM MDT	Severe Thunderstorm Warning	CYS	Converse, Platte	46 min
Aug 15, 11:12 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Niobrara	48 min
Aug 15, 11:32 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Platte	43 min
Aug 15, 11:45 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Platte	30 min
Aug 15, 11:48 PM MDT	Severe Thunderstorm Warning	CYS	Goshen	72 min
Aug 16, 12:13 AM MDT	Severe Thunderstorm Warning	CYS	Goshen, Platte	62 min
Aug 16, 3:08 AM MDT	Fire Weather Watch	CYS		24 hr
Aug 16, 3:08 AM MDT	Fire Weather Watch	CYS		24 hr
Aug 16, 3:58 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Laramie	32 min
Aug 16, 4:34 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Carbon	26 min
Aug 16, 4:38 PM MDT	Special Weather Statement	CYS	Laramie	52 min
Aug 16, 4:57 PM MDT	Special Weather Statement	CYS	Niobrara	48 min
Aug 16, 4:57 PM MDT	Severe Thunderstorm Warning	CYS	Albany, Laramie	33 min
Aug 16, 5:23 PM MDT	Special Weather Statement	CYS	Laramie	52 min
Aug 16, 5:24 PM MDT	Severe Thunderstorm Warning	CYS	Laramie	17 min
Aug 16, 12:40 AM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Morrill, Scotts Bluff, Sioux	80 min
Aug 16, 12:42 AM MDT	Special Weather Statement	CYS	Sioux	48 min
Aug 16, 12:56 AM MDT	Severe Thunderstorm Warning	CYS	Banner, Scotts Bluff, Sioux	79 min
Aug 16, 1:48 AM MDT	Severe Thunderstorm Warning	CYS	Box Butte, Morrill	72 min
Aug 16, 3:49 AM MDT	Special Weather Statement	CYS	Morrill	41 min
Aug 16, 2:56 PM MDT	Special Weather Statement	CYS	Banner	49 min
Aug 16, 3:44 PM MDT	Special Weather Statement	CYS	Kimball	46 min
Aug 16, 5:38 PM MDT	Special Weather Statement	CYS	Kimball	52 min
Aug 16, 5:40 PM MDT	Special Weather Statement	CYS	Banner	50 min
Aug 16, 5:49 PM MDT	Severe Thunderstorm Warning	CYS	Kimball	26 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2019 Every severe thunderstorm warning in 2019

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.