Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 200424

Area Forecast Discussion
National Weather Service Cheyenne WY
1024 PM MDT TUE JUL 19 2016

.SHORT TERM...(This evening through Wednesday)
Issued at 248 PM MDT Tue Jul 19 2016

Scattered showers and isolated thunderstorms firing where the
morning HRRR and NAM had them lighting off this
afternoon...tracking northeast from the Colorado border. Looking
over regional sounding profiles we do see decent CAPE/instability
this afternoon into the early evening, but much less shear than
previous days for organized strong to severe storms. Some showers
and thunderstorms will be capable of producing winds to around 40
mph and potentially some small hail. Best coverages will be
Between Arlington and Kimball and south of Douglas and Lusk
through early evening as warmer midlevel temps should help keep
coverages east and north less. Expect more scattered showers and
thunderstorms west of Wheatland and Cheyenne tomorrow afternoon
where midlevel temperatures will be a bit cooler in the
southwesterly flow aloft on the western periphery of the southern
Plains ridge...with isolated coverages farther east across the
eastern Wyoming Plains and western Nebraska Panhandle.

.LONG TERM...(Wednesday night through Tuesday)
Issued at 248 PM MDT Tue Jul 19 2016

Very warm conditions will persist across the CWA Thursday through
Friday as the area remains on the northern side of the large upper
high centered over the southern CONUS.  Some monsoonal moisture
along with a few weak ripples of energy moving along on the
northern periphery of the upper high will keep chances for mainly
late day convection for the CWA Thursday and Friday. Over the
weekend the upper high slips westward to the desert southwest
turning the upper flow over the CWA westerly and reducing moisture
somewhat. See little convective potential for Saturday while a
weak Pacific front brings some minor cooling. A better chance for
storms...some potentially strong...seen for Sunday as the surface
flow becomes upslope beneath westerly flow aloft and a shortwave
passes across. Similar setup for Monday. Drier and a little warmer
Tuesday as a surface trough moves east over the high plains.


.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1023 PM MDT Tue Jul 19 2016

VFR. Scattered to broken clouds from 8000 to 12000 feet AGL.
Winds gusting from 20 to 23 knots from 15Z to 02Z.


Issued at 248 PM MDT Tue Jul 19 2016

Main forecast challenge here in the near term will be the wind
forecast late tomorrow morning through tomorrow afternoon across
the northern part of fire weather zone 301 (Converse County) where
minimum RH values will be around 10 percent in the afternoon
hours. Right now our thinking is winds will be west at 10 to 15
with gusts around 20 mph tomorrow...below wind portion of the Red
Flag Warning criteria. We will continue to take a look at it as we
go into the evening hours to see if confidence goes higher that we
will see higher winds mixing down tomorrow that zone.
Otherwise...farther to the south and east RH values will be higher
as we see southwesterly flow continue to bring moisture up from
the southwest...and winds will be lighter close to the midlevel


.CYS Watches/Warnings/Advisories...


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