Severe Thunderstorm Warning 280, NWS Cheyenne, WY

Area Forecast Discussion
National Weather Service Cheyenne WY
247 PM MDT Thu Aug 1 2019

.SHORT TERM...(This evening through Saturday)
Issued at 247 PM MDT Thu Aug 1 2019

Showers and a few storms firing over the CWA attm with a few
strong/severe storms mainly over the Panhandle. Activity should
continue to increase the rest of the afternoon with best potential
for severe storms remaining primarily over the Panhandle into this
evening. Locally heavy rain still a possibility as well so will
maintain current FFA as is. Convection should move east and out of
the CWA later tonight as a shortwave drops southeast over the
central plains.

Models showing drier conditions over the CWA Friday through
Saturday as the upper high over the 4 corners area strengthens
some and builds over the area and monsoonal moisture decreases. A
bit of convection hinted over the southern mtns Friday afternoon
so shaded some low pops there. Otherwise seasonably warm
conditions continuing.

.LONG TERM...(Saturday night through Thursday)
Issued at 247 PM MDT Thu Aug 1 2019

Monsoonal moisture increases again Sunday as the upper high
weakens a bit and settles southward. The CWA then resides more
under a northwesterly upper flow next week with periodic impulses
dropping across the region. This will return chances for mainly
afternoon and evening showers and storms on a daily basis. Cooler
early next week then warmer again by midweek, still close to
seasonal averages.

&&

.AVIATION...(For the 18Z TAFS through Friday morning)
Issued at 1125 AM MDT Thu Aug 1 2019

Current KCYS radar loop shows mainly scattered rain showers across
most of southeast Wyoming and western Nebraska late this morning,
with a few embedded thunderstorms across the northern NE panhandle.
All models indicate shower and thunderstorm activity increase in
coverage and intensity by the middle of this afternoon through late
this evening. Thunderstorms should develop near KLAR and KCYS
between 19z to 21z, and then move east across the Nebraska terminals
between 22z to 02z Friday. Very heavy rainfall and frequent
lightning are the primary concerns with IFR conditions possible in
the heaviest thunderstorms. Once this activity moves into central
Nebraska, another round of fog is possible for KSNY, KBFF, and KAIA
by 12z Friday morning.

&&

.FIRE WEATHER...
Issued at 247 PM MDT Thu Aug 1 2019

Showers and thunderstorms are expected over most of the area this
evening before ending later tonight. Wetting rains are likely
with locally heavy rainfall possible especially over the
Panhandle. Drier weather looks to set in Friday and Saturday
before rain chances increase again Sunday into next week.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Flash Flood Watch until midnight MDT tonight for WYZ101-102-108.

NE...Flash Flood Watch until midnight MDT tonight for NEZ002-003-
     019>021-054-055-095-096.

&&

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

Hazardous Weather Outlook
National Weather Service Cheyenne WY
1115 AM MDT Thu Aug 1 2019

WYZ104-105-109>115-020930-
Ferris/Seminoe/Shirley Mountains-Shirley Basin-
Central Carbon County-North Snowy Range Foothills-
Southwest Carbon County-Sierra Madre Range-
Upper North Platte River Basin-Snowy Range-Laramie Valley-
1115 AM MDT Thu Aug 1 2019

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

.DAY ONE...TODAY AND TONIGHT

Scattered showers and a few thunderstorms are expected this
afternoon, decreasing in coverage this evening. Some of the storms
may produce brief moderate to heavy rainfall, small hail and gusty
outflow winds.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

Isolated afternoon and evening thunderstorms Friday through Sunday
will become more scattered Monday through Wednesday. Severe weather
is not expected.

.Spotter information statement...

Spotter activation will not be needed.

NEZ002-003-019>021-054-055-095-096-WYZ101>103-106>108-116>119-
020930-
Dawes-Box Butte-Scotts Bluff-Banner-Morrill-Kimball-Cheyenne-
North Sioux-South Sioux-Converse County Lower Elevations-
Niobrara County-North Laramie Range-
Central Laramie Range and Southwest Platte County-
East Platte County-Goshen County-South Laramie Range-
South Laramie Range Foothills-Central Laramie County-
East Laramie County-
1115 AM MDT Thu Aug 1 2019

This hazardous weather outlook is for the western Nebraska
Panhandle...east central Wyoming and southeast Wyoming.

.DAY ONE...TODAY AND TONIGHT

Scattered to numerous showers and thunderstorms are expected this
afternoon into this evening.  A few storms may be strong to severe
across the high plains with hail gusty outflow winds the main
threats.  Ample moisture in the atmosphere and may yield rainfall
rates in excess of an inch per hour. This may lead to localized
flash flooding. A Flash Flood Watch is in effect this afternoon and
evening for portions of southeast Wyoming and all of the western
Nebraska Panhandle.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

Widely scattered afternoon and evening thunderstorms will develop
over the higher terrain of southeast Wyoming mainly Saturday and
Sunday.  Afternoon and evening thunderstorm chances will increase
Monday through Wednesday. The threat for severe weather is low.

.Spotter information statement...

Spotter activation is not expected at this time.

Special Weather Statement
National Weather Service Cheyenne WY
200 PM MDT Thu Aug 1 2019

NEZ019>021-012045-
Scotts Bluff NE-Morrill NE-Banner NE-
200 PM MDT Thu Aug 1 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN SCOTTS BLUFF...
SOUTHWESTERN MORRILL AND NORTHEASTERN BANNER COUNTIES UNTIL 245 PM
MDT...

At 200 PM MDT, Doppler radar was tracking a strong thunderstorm near
Harrisburg, or 21 miles south of Scottsbluff, moving northeast at 15
mph.

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

Locations impacted include...
Harrisburg and McGrew.

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.

&&

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
the Panhandle of Nebraska.

LAT...LON 4147 10369 4157 10378 4182 10345 4145 10324
TIME...MOT...LOC 2000Z 236DEG 14KT 4156 10363

Trudel

Special Weather Statement
National Weather Service Cheyenne WY
251 PM MDT Thu Aug 1 2019

NEZ003-096-012130-
Box Butte NE-South Sioux NE-
251 PM MDT Thu Aug 1 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN BOX BUTTE AND
SOUTHEASTERN SIOUX COUNTIES UNTIL 330 PM MDT...

At 250 PM MDT, Doppler radar was tracking a strong thunderstorm 8
miles northwest of Kilpatrick Lake, or 23 miles northeast of
Scottsbluff, moving east at 10 mph.

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

This strong thunderstorm will be near...
  Kilpatrick Lake around 330 PM MDT.

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.

&&

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
the Panhandle of Nebraska.

LAT...LON 4212 10351 4223 10355 4235 10315 4204 10310
TIME...MOT...LOC 2050Z 261DEG 7KT 4216 10343

Trudel

Special Weather Statement
National Weather Service Cheyenne WY
259 PM MDT Thu Aug 1 2019

NEZ020-021-054-055-012145-
Kimball NE-Cheyenne NE-Morrill NE-Banner NE-
259 PM MDT Thu Aug 1 2019

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN CHEYENNE...
NORTHEASTERN KIMBALL...SOUTHWESTERN MORRILL AND SOUTHEASTERN BANNER
COUNTIES UNTIL 345 PM MDT...

At 259 PM MDT, Doppler radar was tracking a strong thunderstorm 11
miles southwest of Redington, or 20 miles northeast of Kimball,
moving southeast at 10 mph.

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

This storm will remain over mainly rural areas of northwestern
Cheyenne, northeastern Kimball, southwestern Morrill and southeastern
Banner Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
the Panhandle of Nebraska.

LAT...LON 4151 10364 4162 10355 4157 10318 4129 10335
TIME...MOT...LOC 2059Z 295DEG 8KT 4150 10348

Trudel

Special Weather Statement
National Weather Service Cheyenne WY
325 PM MDT Thu Aug 1 2019

NEZ054-055-012215-
Kimball NE-Cheyenne NE-
325 PM MDT Thu Aug 1 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN CHEYENNE AND EASTERN
KIMBALL COUNTIES UNTIL 415 PM MDT...

At 324 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Kimball to 12 miles east of Panorama
Point. Movement was east at 20 mph.

Penny size hail and winds in excess of 40 mph will be possible with
these storms.

Strong thunderstorms will be near...
  Kimball and Kimball Airport around 330 PM MDT.
  Dix around 345 PM MDT.

This includes Interstate 80 in Nebraska between mile markers 18 and
44.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These storms 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 Severe Thunderstorm Watch remains in effect until 900 PM MDT for
the Panhandle of Nebraska.

LAT...LON 4131 10366 4134 10312 4100 10334 4100 10385
TIME...MOT...LOC 2124Z 248DEG 16KT 4126 10362 4096 10380

Trudel