Hail and Damaging Wind in Wyoming, May 29, 2024

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
137 PM MDT Wed May 29 2024

.KEY MESSAGES...

- Thunderstorms this afternoon and evening; Severe storms are
  expected with damaging wind and large hail the primary hazards.

- Active pattern continues through the weekend with daily chances
  of showers and storms.

- Trending warmer by Saturday, with seasonable to above average
  temperatures expected next week.

&&

.DISCUSSION...(This Evening Through Wednesday)
Issued at 134 PM MDT Wed May 29 2024

Upper level analysis shows upper ridge sliding eastward into the
Upper Midwest with upper trough axis centered through central
Idaho. Water vapor imagery shows shortwave pushing into eastern
Montana with ascent notable on IR/WV beginning to overspread
Montana and Wyoming. At the surface, diffuse low pressure/surface
trough extends from northeastern Wyoming southward into eastern
Colorado with a cold front extending from central Montana into
western Wyoming. A band of convection has formed east of the
Bighorns and has pushed into Campbell County.

Additional thunderstorms are expected to form across northeastern
Wyoming and western South Dakota over the next 1-3 hours, spreading
eastward through the afternoon and evening, some of which are
expected to be strong to severe. Ample instability is in place
(MUCAPE ~1000-2000 J/kg) with steep lapse rates (~8-9C/km) atop a
well-mixed boundary layer. Given the dry boundary layer, MLCAPE is
muted (~500-1250 J/kg) and MLCIN has been slow to erode across
western SD. Expect the remain MLCIN to weaken over the next 1-2 hours
with continued heating and increasing upper ascent. Additionally,
the dry/well-mixed BL has resulted in DCAPE ~1200 J/kg (per SPC
mesoanalysis), which will persist through the evening hours. Forecast
soundings show rather meager bulk shear (EBWD ~25-30 knots);
hodographs show ample curvature and shear within the lowest 3 km,
although modest winds aloft will limit the overall shear available.
Storm mode is expected to be multi-cellular with transient
supercellular characteristics. Given these ingredients coupled with
anticipated storm mode, expect mainly a damaging wind threat through
the evening. Regarding hail potential - modest shear will limit storm
organization, although sufficient instability exists for large hail.
Additionally, forecast soundings show relative lack of CAPE below the
freezing layer, which will result in increased residence time for
any parcel within the hail growth zone - this will help mitigate the
lack of shear throughout the cloud bearing layer. Ultimately, expect
the best hail threat will be limited to any stronger, longer lasting
updraft cores.

Deterministic and ensemble guidance both depict fairly active, zonal
flow through at least mid-week next week. This would result in near
daily chances of showers and thunderstorms the rest of this week
into next week.

Cooler temperatures will prevail tomorrow and Friday behind
the surface cold front before more zonal/southwesterly flow resumes
for next week and temperatures warm. Temperatures across the
higher elevations of the Black Hills are likely to fall into the
mid 30s tonight and Thursday night; some snow may mix in with rain
across the higher elevations of the Black Hills Thursday
night/Friday morning, although no accumulation is expected.
Ensembles and cluster analysis highlight broad ridging building
across the western half of the country by mid-week next week.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Thursday)
Issued At 1043 AM MDT Wed May 29 2024

Breezy southeasterly winds will continue across the western SD
plains this afternoon. Scattered thunderstorms are expected to
develop across northeastern WY early this afternoon, spreading
eastward into western SD later this afternoon and early evening
with the surface trough. At this time expecting storms to develop
just east of KGCC, but moving into KRAP around 00Z. Another round
of showers/storms will develop later this evening with the cold
front, which could affect both KGCC and KRAP. MVFR/IFR conditions
with gusty, erratic winds and hail may be encountered in and
around any storms. Additionally, some brief LLWS will be possible
across south central SD tonight as the trough moves through.
Behind the cold front, winds will become northwesterly and
somewhat breezy. Showers/storms will dissipate early Thursday
morning.

&&

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

DISCUSSION/KEY MESSAGES...SE
AVIATION...Pojorlie

Hazardous Weather Outlook
National Weather Service Rapid City SD
329 AM MDT Wed May 29 2024

SDZ001-002-012-013-024>031-041-042-072>076-078-WYZ057-059-060-
301300-
Harding-Northern Perkins-Butte-Northern Meade Co Plains-
Northern Black Hills-Northern Foothills-Rapid City-
Southern Foothills-Central Black Hills-Southern Black Hills-
Custer Co Plains-Pennington Co Plains-Western Fall River-
Northern Oglala Lakota-Sturgis/Piedmont Foothills-
Southern Meade Co Plains-Hermosa Foothills-Eastern Fall River-
Southern Oglala Lakota-Southern Perkins-Wyoming Black Hills-
Newcastle-Northeastern Crook-
329 AM MDT Wed May 29 2024

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

.DAY ONE...Today and Tonight

There is a slight risk (level 2 of 5) of severe thunderstorms
today, meaning that scattered severe storms are possible. Primary
hazards include damaging wind gusts and large hail.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

There will be near daily chances for thunderstorms through the
weekend into next week. Severe weather is not expected at this
time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed today.

&&

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

SDZ014-032-043-044-046-047-077-WYZ054>056-058-301300-
Ziebach-Haakon-Northern Jackson-Bennett-Mellette-Todd-
Southern Jackson-Northern Campbell-Southern Campbell-
Western Crook-Weston County Plains-
329 AM MDT Wed May 29 2024 /429 AM CDT Wed May 29 2024/

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

.DAY ONE...Today and Tonight

There is a marginal risk (level 1 of 5) of severe thunderstorms
today, meaning that isolated severe storms are possible. Primary
hazards include damaging wind and large hail.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

There will be near daily chances for thunderstorms through the
weekend into next week. Severe weather is not expected at this
time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed today.

&&

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

SDZ049-301300-
Tripp-
429 AM CDT Wed May 29 2024

This Hazardous Weather Outlook is for portions of south central
South Dakota.

.DAY ONE...Today and Tonight

There is a chance for thunderstorms this afternoon and evening.
While some storms may be strong with gusty winds and hail, severe
weather is not expected at this time.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Isolated strong to severe thunderstorms are possible on Thursday.
Primary hazards will be damaging winds and large hail.

There will be near daily chances for thunderstorms Friday through
the weekend into next week. Severe weather is not expected at
this time.

.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

Special Weather Statement
National Weather Service Rapid City SD
227 PM MDT Wed May 29 2024

WYZ054>058-292115-
Northern Campbell WY-Wyoming Black Hills WY-Western Crook WY-
Southern Campbell WY-Weston County Plains WY-
227 PM MDT Wed May 29 2024

...STRONG THUNDERSTORMS WILL IMPACT EAST CENTRAL CAMPBELL...
NORTHWESTERN WESTON AND SOUTHWESTERN CROOK COUNTIES THROUGH 315 PM
MDT...

At 226 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from 2 miles southwest of Oshoto to 10 miles
southeast of Coal Creek Mine. Movement was east at 20 mph.

HAZARD...Wind gusts of 50 to 55 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Strong thunderstorms will be near...
  Moorcroft around 230 PM MDT.
  Keyhole Reservoir around 235 PM MDT.
  Carlile around 245 PM MDT.
  Pine Haven around 250 PM MDT.
  Devils Tower National Monument around 255 PM MDT.

This includes Interstate 90 in Wyoming between Mile Markers 141 and
167.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
northeastern Wyoming.

&&

LAT...LON 4465 10468 4383 10472 4387 10528 4455 10518
TIME...MOT...LOC 2026Z 249DEG 17KT 4457 10499 4391 10510

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...55 MPH

Pojorlie

Preliminary Local Storm Report
National Weather Service Rapid City SD
231 PM MDT Wed May 29 2024

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

0215 PM     Hail             3 NNE Rozet             44.32N 105.19W
05/29/2024  E1.25 inch       Campbell           WY   Trained Spotter

            Accompanied by 40 mph winds and heavy rain

&&

NWS

Preliminary Local Storm Report
National Weather Service Rapid City SD
254 PM MDT Wed May 29 2024

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

0241 PM     Tstm Wnd Gst     4 ESE Rozet             44.26N 105.13W
05/29/2024  M57 mph          Campbell           WY   Trained Spotter

            Accompanied by dime size hail and brief heavy rain

&&

NWS

Preliminary Local Storm Report
National Weather Service Rapid City SD
321 PM MDT Wed May 29 2024

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

0251 PM     Non-Tstm Wnd Gst 8 E Prairie City        45.53N 102.64W
05/29/2024  M50 mph          Perkins            SD   Mesonet

&&

WFO UNR

Special Weather Statement
National Weather Service Rapid City SD
330 PM MDT Wed May 29 2024

SDZ001-012-292215-
Butte SD-Harding SD-
330 PM MDT Wed May 29 2024

...STRONG THUNDERSTORMS WILL IMPACT WESTERN HARDING AND NORTHWESTERN
BUTTE COUNTIES THROUGH 415 PM MDT...

At 330 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from 17 miles east of Ekalaka to 6 miles west of
Antelope Butte. Movement was northeast at 20 mph.

HAZARD...Wind gusts of 50 to 55 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Strong thunderstorms will be near...
  Camp Crook, Gustave, and West Short Pines around 335 PM MDT.
  Harding around 355 PM MDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
northwestern South Dakota...and northeastern Wyoming.

&&

LAT...LON 4501 10367 4492 10405 4499 10407 4501 10404
      4594 10404 4595 10394
TIME...MOT...LOC 2130Z 226DEG 15KT 4591 10420 4502 10393

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...55 MPH

Pojorlie

Special Weather Statement
National Weather Service Rapid City SD
412 PM MDT Wed May 29 2024

SDZ001-012-013-292300-
Butte SD-Northern Meade Co Plains SD-Harding SD-
412 PM MDT Wed May 29 2024

...STRONG THUNDERSTORMS WILL IMPACT SOUTHWESTERN HARDING...EASTERN
BUTTE AND CENTRAL MEADE COUNTIES THROUGH 500 PM MDT...

At 412 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from 3 miles northwest of East Short Pines to 4
miles northwest of Owl Butte. Movement was northeast at 20 mph.

HAZARD...Wind gusts of 50 to 55 mph and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Strong thunderstorms will be near...
  Redig, Crow Buttes, Haystack Buttes, and East Short Pines around
  420 PM MDT.
  Hoover and Dears Ears Butte around 440 PM MDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
northwestern and west central South Dakota.

&&

LAT...LON 4560 10353 4474 10289 4466 10339 4534 10392
TIME...MOT...LOC 2212Z 245DEG 17KT 4538 10377 4477 10329

MAX HAIL SIZE...0.88 IN
MAX WIND GUST...55 MPH

Pojorlie