Alert archive / Wyoming / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 167, NWS Cheyenne, WY

July 4, 2019Albany County, Platte County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jul 4, 2019, 3:21 PM MDT for Albany County, Platte County, Wyoming. It was in force for 24 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 4, 2019, 3:21 PM MDT (21:21 UTC)
Expired
Jul 4, 2019, 3:45 PM MDT
In force
24 min
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Albany County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 94 km from the middle of the area, began a volume at 21:23 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 4, 2:37 PM MDTTornado WatchSPC9 hr

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 9.4 hours before the alert went out and 283 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, Riverton, WY at 12:00Z on 2019-07-04Temperature 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 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 12:00Z on 2019-07-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 144 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
1001 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
144 m²/s²
0-3 km storm-relative helicity
308 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 Cheyenne, WY wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 4, 12:07 PM MDT, 3 hours 14 minutes earlier.

Area forecast discussion, Jul 4, 12:07 PM MDT, 3 hours 14 minutes before
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Hazardous weather outlook, Jul 4, 3:29 AM MDT, 11 hours 52 minutes before
Hazardous Weather Outlook
National Weather Service Cheyenne WY
329 AM MDT Thu Jul 4 2019

NEZ002-003-019>021-054-055-095-096-WYZ101>119-050930-
Dawes-Box Butte-Scotts Bluff-Banner-Morrill-Kimball-Cheyenne-
North Sioux-South Sioux-Converse County Lower Elevations-
Niobrara County-North Laramie Range-
Ferris/Seminoe/Shirley Mountains-Shirley Basin-
Central Laramie Range and Southwest Platte County-
East Platte County-Goshen 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-
329 AM MDT Thu Jul 4 2019

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

.DAY ONE...TODAY AND TONIGHT

A slight to enhanced risk of severe thunderstorms exists this
afternoon and evening across most of the region east of Carbon
County.

A Flash Flood Watch is in effect from 3 PM MDT to midnight for
most of the Nebraska Panhandle as well as Niobrara and Goshen
Counties of southeast Wyoming.

Scattered to numerous thunderstorms will develop this afternoon
and continue into the overnight hours tonight. Some of the storms
will likely become severe, producing quarter size hail or larger
as well as wind gusts in excess of 60 mph. Some of the
thunderstorms will produce locally heavy rain and possible flash
flooding due to their slow movement.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

Isolated to scattered afternoon and evening thunderstorms can be
expected nearly every day. There is a marginal risk of severe
thunderstorms for Friday and Saturday, as a few of the storms may
become severe, producing large hail and damaging winds.

.Spotter information statement...

Spotter activation may be necessary this afternoon and evening.

Rubin

In the hours before

Special weather statement, Jul 4, 12:35 PM MDT, 2 hours 46 minutes before
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Special weather statement, Jul 4, 3:06 PM MDT, 15 minutes before
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Special weather statement, Jul 4, 3:10 PM MDT, 11 minutes before
Special Weather Statement
National Weather Service Cheyenne WY
310 PM MDT Thu Jul 4 2019

WYZ103-106-115-042215-
Central Laramie Range and Southwest Platte County WY-
North Laramie Range WY-Laramie Valley WY-
310 PM MDT Thu Jul 4 2019

...SPECIAL WEATHER STATEMENT...

At 310 PM MDT, Doppler radar was tracking a strong thunderstorm 9
miles southeast of Wheatland Reservoir 3, or 33 miles north of
Laramie, moving east at 15 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 east central Albany
and southwestern Platte Counties.

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.

&&

A Tornado Watch remains in effect until 1000 PM MDT for southeastern
Wyoming.

LAT...LON 4171 10568 4187 10570 4216 10527 4177 10515
TIME...MOT...LOC 2110Z 260DEG 12KT 4179 10557

Worley
Special weather statement, Jul 4, 3:19 PM MDT, 2 minutes before
Special Weather Statement
National Weather Service Cheyenne WY
319 PM MDT Thu Jul 4 2019

WYZ101-103-042200-
Converse County Lower Elevations WY-North Laramie Range WY-
319 PM MDT Thu Jul 4 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL CONVERSE COUNTY
UNTIL 400 PM MDT...

At 319 PM MDT, Doppler radar was tracking a strong thunderstorm 7
miles southeast of Laprele Reservoir, or 13 miles southwest of
Douglas, moving northeast at 20 mph.

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

Locations impacted include...
Douglas and Laprele Reservoir.

This includes Interstate 25 in Wyoming between mile markers 129 and
147.

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.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

A Tornado Watch remains in effect until 1000 PM MDT for east central
Wyoming.

LAT...LON 4249 10553 4261 10571 4291 10542 4272 10515
TIME...MOT...LOC 2119Z 222DEG 16KT 4261 10556

Lyons

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 3, 6:29 PM MDTSpecial Weather StatementCYSLaramie46 min
Jul 3, 7:10 PM MDTSpecial Weather StatementCYSNiobrara50 min
Jul 3, 9:38 PM MDTSevere Thunderstorm WarningCYSConverse52 min
Jul 3, 10:13 PM MDTSevere Thunderstorm WarningCYSConverse, Niobrara47 min
Jul 3, 10:58 PM MDTSevere Thunderstorm WarningCYSNiobrara47 min
Jul 3, 11:12 PM MDTSpecial Weather StatementCYSConverse48 min
Jul 3, 11:21 PM MDTSevere Thunderstorm WarningCYSConverse24 min
Jul 3, 11:45 PM MDTSevere Thunderstorm WarningCYSConverse45 min
Jul 4, 12:25 AM MDTSpecial Weather StatementCYSNiobrara50 min
Jul 4, 1:23 AM MDTSpecial Weather StatementCYSNiobrara52 min
Jul 4, 3:12 AM MDTFlash Flood WatchCYSGoshen, Niobrara21 hr
Jul 4, 6:30 AM MDTSpecial Weather StatementCYSConverse45 min
Jul 4, 3:06 PM MDTSpecial Weather StatementCYSLaramie54 min
Jul 4, 3:10 PM MDTSpecial Weather StatementCYSAlbany65 min
Jul 4, 3:19 PM MDTSpecial Weather StatementCYSConverse41 min
Jul 4, 3:37 PM MDTSevere Thunderstorm WarningCYSAlbany, Platte23 min
Jul 4, 3:54 PM MDTSevere Thunderstorm WarningCYSAlbany, Platte66 min
Jul 4, 3:55 PM MDTSpecial Weather StatementCYSConverse50 min
Jul 4, 4:01 PM MDTSpecial Weather StatementCYS44 min
Jul 4, 4:08 PM MDTSpecial Weather StatementCYSConverse52 min
Jul 4, 4:27 PM MDTSevere Thunderstorm WarningCYSCarbon21 min
Jul 4, 4:32 PM MDTTornado WarningCYSLaramie, Platte28 min
Jul 4, 4:49 PM MDTSpecial Weather StatementCYSConverse41 min
Jul 4, 4:57 PM MDTTornado WarningCYSPlatte48 min
Jul 4, 5:29 PM MDTSpecial Weather StatementCYSConverse46 min
Jul 4, 5:34 PM MDTSpecial Weather StatementCYSConverse41 min
Jul 4, 5:42 PM MDTSpecial Weather StatementCYSConverse48 min
Jul 4, 5:45 PM MDTSevere Thunderstorm WarningCYSConverse, Platte45 min
Jul 4, 5:47 PM MDTSpecial Weather StatementCYSGoshen43 min
Jul 4, 5:53 PM MDTSevere Thunderstorm WarningCYSGoshen, Laramie, Platte28 min
Jul 3, 6:12 PM MDTSpecial Weather StatementCYSBox Butte48 min
Jul 3, 6:25 PM MDTSevere Thunderstorm WarningCYSBox Butte, Morrill35 min
Jul 3, 7:00 PM MDTSpecial Weather StatementCYSBox Butte45 min
Jul 3, 8:30 PM MDTSpecial Weather StatementCYSKimball60 min
Jul 3, 9:32 PM MDTSpecial Weather StatementCYSSioux58 min
Jul 3, 9:58 PM MDTSevere Thunderstorm WarningCYSDawes32 min
Jul 3, 10:10 PM MDTSpecial Weather StatementCYSCheyenne50 min
Jul 3, 11:24 PM MDTSpecial Weather StatementCYSCheyenne36 min
Jul 4, 12:30 AM MDTSpecial Weather StatementCYSMorrill45 min
Jul 4, 12:39 AM MDTSpecial Weather StatementCYSDawes51 min
Jul 4, 12:35 PM MDTSpecial Weather StatementCYSScotts Bluff55 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2019Every 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.