Alert archive / Wyoming / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 51, NWS Rapid City, SD

June 13, 2021Weston County, Wyoming

NWS Rapid City, SD issued this severe thunderstorm warning at Jun 13, 2021, 6:00 PM MDT for Weston County, Wyoming. It was in force for 44 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: Jun 13, 2021, 6:00 PM MDT (00:00 UTC)
Expired: Jun 13, 2021, 6:44 PM MDT
In force: 44 min
Issued by: NWS Rapid City, SD
Area: Storm-based polygon
Hail: 1.5 in
Wind: 50.0 mph

County Weston County, WY

The radar

The Rapid City radar (KUDX), 143 km from the middle of the area, began a volume at 00:03 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, 0.0 hours before the alert went out and 137 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: 1422 J/kg
Mixed-layer CIN: -91 J/kg
Mixed-layer LCL: 1895 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 139 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.9

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 Rapid City, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 13, 5:13 PM MDT, 47 minutes earlier.

Area forecast discussion, Jun 13, 5:13 PM MDT, 47 minutes before

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
513 PM MDT Sun Jun 13 2021

.DISCUSSION...(This Evening Through Sunday)
Issued at 237 PM MDT Sun Jun 13 2021

Strong upper ridge axis is building over the northern Plains with
warm air advection moving toward the forecast area. Very small
wave embedded in southwest flow moving into southwestern WY may
trigger some thunderstorms over extreme southern SD this evening,
where 2000-3000 j/kg CAPE and steep lapse rates exist, although
higher potential will be in NE. An isolated thunderstorm may still
develop over the southern Black Hills. Surface boundary is
slowly sinking southward through southern SD as evident of the
northward moving CU field with the higher dewpoints and southwest
winds stopped at the boundary with northeast winds and lower
dewpoints to the north.

Heights build over the northern Plains through Tuesday as upper
trof deepens over the northwestern US. Next wave rides up
southwest flow into northeastern WY tomorrow afternoon for
isolated thunderstorms again ahead of lee trof. Ridge flattens as
the upper low tracks across southern Canada with cold front moves
through Wednesday, with temperatures cooling.

&&

.AVIATION...(For the 00Z TAFS Through 00Z Monday Evening)
Issued At 512 PM MDT Sun Jun 13 2021

Mainly VFR conditions expected through the TAF period. Isolated
to scattered thunderstorms will be possible in the evening hours,
mainly from the Black Hills southeast, with local MVFR
conditions.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...None.
WY...None.
&&

DISCUSSION...55
AVIATION...JC

Hazardous weather outlook, Jun 13, 4:23 AM MDT, 13 hours 37 minutes before

Hazardous Weather Outlook
National Weather Service Rapid City SD
423 AM MDT Sun Jun 13 2021

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058-
071-141300-
Harding-Perkins-Butte-Northern Meade Co Plains-Ziebach-
Northern Black Hills-Northern Foot Hills-Rapid City-
Southern Foot Hills-Central Black Hills-Southern Black Hills-
Custer Co Plains-Pennington Co Plains-Haakon-Fall River-
Oglala Lakota-Jackson-Bennett-Mellette-Todd-Tripp-
Sturgis/Piedmont Foot Hills-Southern Meade Co Plains-
Hermosa Foot Hills-Northern Campbell-Southern Campbell-
Western Crook-Wyoming Black Hills-Weston-Northeastern Crook-
423 AM MDT Sun Jun 13 2021 /523 AM CDT Sun Jun 13 2021/

This Hazardous Weather Outlook is for portions of western South
Dakota and northeastern Wyoming.

.DAY ONE...Today and Tonight

Isolated thunderstorms are possible today, mainly late this
afternoon and early this evening from the Black Hills into far
southern South Dakota. Isolated strong storms with some hail and
gusty winds may occur.

.DAYS TWO THROUGH SEVEN...Monday through Saturday

There is a marginal risk of severe thunderstorms from northeast
Wyoming into far western South Dakota later Monday afternoon and
evening. Large hail and damaging winds will be the main risk.

Hot weather is expected Monday through Wednesday with highs well
into the 90s to around 100 degrees. Near critical fire weather
conditions may occur Monday due to very low relative humidities
and breezy southeast winds.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today.

&&

Stay tuned to NOAA weather radio for further updates...or check
our web site at weather.gov/rapidcity

In the hours before

Special weather statement, Jun 13, 4:09 PM MDT, 1 hour 51 minutes before

Special Weather Statement
National Weather Service Rapid City SD
409 PM MDT Sun Jun 13 2021

WYZ058-132245-
Weston WY-
409 PM MDT Sun Jun 13 2021

...STRONG THUNDERSTORM OVER NORTH CENTRAL WESTON COUNTY...

At 409 PM MDT, Doppler radar was tracking a strong thunderstorm 7
miles south of Upton, or 22 miles northwest of Newcastle, moving east
at 10 mph.

Penny size hail will be possible with this storm.

Locations impacted include...
Osage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek safe shelter inside a building or vehicle until this storm has
passed.

&&

LAT...LON 4391 10470 4404 10470 4413 10445 4392 10440
TIME...MOT...LOC 2209Z 252DEG 8KT 4399 10460

JC

Local storm report, Jun 13, 5:42 PM MDT, 18 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
542 PM MDT SUN JUN 13 2021

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

0503 PM     HAIL             2 NW OSAGE              44.00N 104.45W
06/13/2021  E1.50 INCH       WESTON             WY   PUBLIC

&&

CALDERON

The office that day

Everything else NWS Rapid City, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 13, 7:58 PM MDT	Severe Thunderstorm Warning	UNR	Bennett, Todd	62 min
Jun 13, 9:24 PM MDT	Severe Thunderstorm Warning	UNR	Fall River	29 min
Jun 13, 11:45 PM MDT	Special Weather Statement	UNR	Mellette	30 min
Jun 14, 12:07 AM MDT	Special Weather Statement	UNR	Tripp	53 min
Jun 14, 12:48 AM MDT	Special Weather Statement	UNR	Tripp	57 min
Jun 14, 2:40 PM MDT	Fire Weather Watch	UNR	Campbell, Crook, Weston	12 hr
Jun 14, 5:16 PM MDT	Severe Thunderstorm Warning	UNR	Campbell	29 min
Jun 14, 5:27 PM MDT	Severe Thunderstorm Warning	UNR	Campbell	48 min
Jun 14, 5:44 PM MDT	Severe Thunderstorm Warning	UNR	Campbell	46 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2021 Every severe thunderstorm warning in 2021

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.