Special Weather Statement, NWS Cheyenne, WY

Area Forecast Discussion
National Weather Service Cheyenne WY
611 PM MDT Mon Jun 29 2020

.SHORT TERM...(This evening through Wednesday night)
Issued at 233 PM MDT Mon Jun 29 2020

Quiet so far over the CWA with an upper low quite evident on
satellite spinning over Idaho. Latest HRRR showing some convection
firing over western areas late this afternoon and continuing this
evening while moving generally northward, but not reaching into
the Neb Panhandle. The southerly flow aloft would favor this and
have trimmed pops down over the Panhandle for tonight. Otherwise a
cold front will move across the CWA tonight while the upper low
drifts northward with convection continuing over northern parts of
the CWA after midnight ahead of a shortwave that will be over
central Wy.

Cooler Tuesday with some breezy conditions especially
over the plains. Dry air will hinder convection but a few showers
and storms possible in the afternoon as the shortwave moves
across. Rather cool by Weds morning with mins in the 40s common.
Warmer and still mainly dry Weds under a wsw flow aloft.

.LONG TERM...(Thursday through Monday)
Issued at 233 PM MDT Mon Jun 29 2020

Little change in the weather pattern overall through the weekend
with nearly daily chances for showers and storms as the CWA will
be under a swly flow aloft with weak disturbances lifting across
from time to time, especially Saturday through Monday when higher
moisture looks to advect over the area. Temperatures remaining
warm, being a bit above seasonal averages.

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 558 PM MDT Mon Jun 29 2020

VFR conditions under a mostly cloudy sky this evening. Isolated
showers and thunderstorms will continue through about 30/06Z, with
gusty and erratic winds up to 45 mph the main concern. Breezy
conditions tomorrow out of the WSW across southeast Wyoming and
the WNW across the western Nebraska Panhandle beginning around
sunrise as a generally dry, strong cold front passes through the
region. Scattered showers expected generally between 30/21Z and
31/06Z across portions of the region. Gusty/erratic winds will be
the main concern once again.

&&

.FIRE WEATHER...
Issued at 233 PM MDT Mon Jun 29 2020

Isolated showers and storms are possible overnight as a cold
front moves east across the area with the best chance being over
northern districts. Tuesday will be breezy over much of the area
but cooler with higher min RHs. Warmer weather is then expected
for the rest of the week with isolated late day showers and storms
possible. Elevated fire weather conditions are also expected
midweek as min RHs lower into the teens.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.
&&

SHORT TERM...RE
LONG TERM...RE
AVIATION...AB
FIRE WEATHER...RE

Hazardous Weather Outlook
National Weather Service Cheyenne WY
636 AM MDT Mon Jun 29 2020

NEZ002-003-019>021-054-055-095-096-WYZ101>119-301245-
Dawes-Box Butte-Scotts Bluff County-Banner County-Morrill-
Kimball County-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-
636 AM MDT Mon Jun 29 2020

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

.DAY ONE...TODAY AND TONIGHT

Scattered showers and thunderstorms are expected to develop by mid
afternoon, and persist into the evening and overnight. Widespread
severe weather is not expected. However, some storms may produce
strong gusty winds.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

A few thunderstorms will be possible again on Tuesday.

.Spotter information statement...

Spotter activation is not expected.

Special Weather Statement
National Weather Service Cheyenne WY
442 PM MDT Mon Jun 29 2020

WYZ101-102-292315-
Converse County Lower Elevations WY-Niobrara County WY-
442 PM MDT Mon Jun 29 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN NIOBRARA AND
NORTHEASTERN CONVERSE COUNTIES UNTIL 515 PM MDT...

At 442 PM MDT, Doppler radar was tracking a couple strong
thunderstorms 13 miles south of Dull Center, or 38 miles northeast
of Douglas, moving northeast at 40 mph.

Half inch hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Bill and Dull Center.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

&&

LAT...LON 4315 10491 4314 10514 4320 10533 4350 10508
      4350 10455
TIME...MOT...LOC 2242Z 211DEG 35KT 4322 10498

Mokry

Special Weather Statement
National Weather Service Cheyenne WY
449 PM MDT Mon Jun 29 2020

NEZ002-292330-
Dawes NE-
449 PM MDT Mon Jun 29 2020

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN DAWES COUNTY UNTIL
530 PM MDT...

At 448 PM MDT, Doppler radar was tracking a strong thunderstorm near
Whitney Lake, or 15 miles southwest of Chadron, moving northeast at
15 mph.

Half inch hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Whitney Lake and Whitney.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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.

If on or near Whitney Lake, get out of the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 10 miles
from the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not
be caught on the water in a thunderstorm.

&&

LAT...LON 4268 10323 4272 10333 4282 10344 4298 10340
      4286 10308
TIME...MOT...LOC 2248Z 207DEG 14KT 4273 10328

Mokry

Special Weather Statement
National Weather Service Cheyenne WY
621 PM MDT Mon Jun 29 2020

WYZ106-107-300045-
East Platte County WY-
Central Laramie Range and Southwest Platte County WY-
621 PM MDT Mon Jun 29 2020

...SPECIAL WEATHER STATEMENT...

At 621 PM MDT, Doppler radar was tracking a strong thunderstorm over
Chugwater, or 23 miles south of Wheatland, moving north at 25 mph.

Pea size hail and winds in excess of 30 mph will be possible with
this storm.

Locations impacted include...
Chugwater and Slater.

This includes Interstate 25 in Wyoming between mile markers 50 and
63.

LAT...LON 4168 10466 4169 10477 4168 10484 4176 10484
      4191 10486 4192 10466
TIME...MOT...LOC 0021Z 190DEG 23KT 4174 10479

Mokry