Alert archive / Wyoming / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 237, NWS Cheyenne, WY

July 15, 2019Converse County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jul 15, 2019, 4:15 PM MDT for Converse County, Wyoming. It was in force for 30 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 15, 2019, 4:15 PM MDT (22:15 UTC)
Expired
Jul 15, 2019, 4:45 PM MDT
In force
30 min
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Converse County, WY

The radar

The Cheyenne radar (KCYS), 210 km from the middle of the area, began a volume at 22:18 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 watch it was issued in

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

IssuedProductOfficeLasted
Jul 15, 2:54 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Rapid City, SD (KUNR), launched 12:00Z, 10.3 hours before the alert went out and 244 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, Rapid City, SD at 12:00Z on 2019-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 411 joules per kilogram.LCLLFCEL10008507005003002001001 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, Rapid City, SD at 12:00Z on 2019-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -12 square meters per square second.193958Sfc1 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
411 J/kg
Mixed-layer CIN
-354 J/kg
Mixed-layer LCL
1339 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-12 m²/s²
0-3 km storm-relative helicity
139 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

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 15, 1:07 PM MDT, 3 hours 8 minutes earlier.

Area forecast discussion, Jul 15, 1:07 PM MDT, 3 hours 8 minutes before
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Hazardous weather outlook, Jul 15, 12:51 PM MDT, 3 hours 24 minutes before
Hazardous Weather Outlook
National Weather Service Cheyenne WY
1251 PM MDT Mon Jul 15 2019

NEZ002-003-019>021-054-055-095-096-WYZ101>119-161900-
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-
1251 PM MDT Mon Jul 15 2019

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

There is a marginal risk of severe thunderstorms this afternoon
and evening east of a Laramie to Cheyenne line, with a slight risk
of severe thunderstorms east of a Douglas to Kimball line.

Isolated to scattered thunderstorms will develop this afternoon
and evening. Some of the thunderstorms, especially in the slight
risk area, will likely become strong to severe, producing either
large hail or damaging winds.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

A few thunderstorms may become strong to severe Tuesday afternoon
and evening north of a Lusk to Alliance line. Thunderstorms will
be possible again Wednesday, Saturday and Sunday afternoons and
evenings.

.Spotter information statement...

Spotter activation will not be needed.

Rubin

In the hours before

Special weather statement, Jul 15, 1:29 PM MDT, 2 hours 46 minutes before
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<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
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Special weather statement, Jul 15, 3:26 PM MDT, 49 minutes before
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      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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        The site you requested is temporarily down for maintenance or an unexpected outage.
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        Please try again in a few minutes.
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The office that day

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

IssuedProductOfficeCountiesLasted
Jul 14, 8:02 PM MDTSpecial Weather StatementCYSGoshen43 min
Jul 15, 1:29 PM MDTSpecial Weather StatementCYSLaramie46 min
Jul 15, 3:26 PM MDTSpecial Weather StatementCYSConverse49 min
Jul 15, 4:20 PM MDTSpecial Weather StatementCYSPlatte25 min
Jul 15, 4:42 PM MDTSpecial Weather StatementCYSConverse48 min
Jul 15, 4:47 PM MDTSpecial Weather StatementCYSPlatte28 min
Jul 15, 4:49 PM MDTSpecial Weather StatementCYSNiobrara26 min
Jul 15, 5:07 PM MDTSevere Thunderstorm WarningCYSConverse, Niobrara23 min
Jul 15, 5:16 PM MDTSpecial Weather StatementCYSGoshen29 min
Jul 15, 5:30 PM MDTSpecial Weather StatementCYSNiobrara30 min
Jul 15, 5:35 PM MDTSpecial Weather StatementCYSGoshen40 min
Jul 15, 5:57 PM MDTSevere Thunderstorm WarningCYSNiobrara33 min
Jul 14, 7:42 PM MDTSpecial Weather StatementCYSSioux48 min
Jul 14, 8:25 PM MDTSpecial Weather StatementCYSSioux50 min
Jul 14, 8:30 PM MDTSpecial Weather StatementCYSSioux45 min
Jul 14, 8:37 PM MDTSevere Thunderstorm WarningCYSBox Butte, Dawes, Sioux23 min
Jul 14, 8:58 PM MDTSevere Thunderstorm WarningCYSBox Butte, Dawes, Sioux47 min
Jul 14, 9:33 PM MDTSpecial Weather StatementCYSScotts Bluff42 min
Jul 15, 5:55 PM MDTSpecial Weather StatementCYSScotts Bluff35 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.