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fxus65 kcys 232104 

Area forecast discussion
National Weather Service Cheyenne Wyoming
304 PM MDT Fri Aug 23 2019

issued at 302 PM MDT Fri Aug 23 2019

Severe Thunderstorm Watch for all of the Nebraska Panhandle and
all counties with exception of Carbon in southeast Wyoming till 10


Short term...(this evening through saturday)
issued at 134 PM MDT Fri Aug 23 2019

Based off the latest satellite and radar imagery, a lower cloud
deck across much of the NE Panhandle is slowly eroding as diurnal
cumulus begins to build shaping the area up for another round of
showers and thunderstorms some severe this afternoon. A slight
risk by the Storm Prediction Center with all three main severe types of hail, damaging
winds, and an isolated tornado threat are possible. A watch of
some sort may be warranted later today so keep monitoring
weather.Gov/cys for the latest forecast information.

The upper level trough in association with the threat of storms
today will continue eastward with overall deep bulk shear from 30
kt to 45 kt behind it and 10 to 20 knots ahead of it. The slower
storm motion will be sufficient enough to warrant some flooding
concerns as precipitable water values remain under an inch over southeast
Wyoming and an inch to 1.2 inches over the NE Panhandle. Strong
surface-based cape suggest upwards of 4500 j/kg over southeast Wyoming for
strong to severe potential even with daytime highs barely reaching
into the low 80s and higher dewpoints over the west central part
of the Panhandle in the mid 60s. Pop and quantitative precipitation forecast fields were generated
using a blend of the namnest, hrrr, and nbm. Conditions will dry
up and become clearer later this evening.

Fire weather wise, breezy winds and low rhs across western Carbon
County have been persistent and consistent enough to warrant a red
flag warning for fwz 303 and 304 in western Carbon County till 8
PM MDT tonight. Similar conditions will continue for Saturday and
Sunday with winds on Sunday gusting across Carbon County from the
mid 30s to the low 40s. Those winds coupled with low relative humidity values
will be sufficient for quick fire growth and fire intensity.

Long term...(saturday through thursday)
issued at 245 am MDT Fri Aug 23 2019

Latest models/ensembles are in good agreement with a increasing west
to northwest flow aloft as a upper trough over west/central Canada
gradually builds south and east into the north-central Continental U.S. This
weekend into early next week. This system will push a fairly strong
cold front for this time of year south and east into the County Warning Area Sunday
night/early Monday. Scattered showers and isolated thunderstorms will
accompany the frontal passage Sunday night east of the Wyoming Front
Range. The remainder of the long term will be dry, except for widely
scattered showers and thunderstorms from the southeast Wyoming plains
into the Nebraska Panhandle. Temperatures will average 5 to 10 degrees
below seasonal normals.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1151 am MDT Fri Aug 23 2019

VFR conditions will continue at all terminal until later in the
afternoon when thunderstorms in the vicinity is possible in the kcys and klar terminals.
Expect gusty winds to continue in the Panhandle this afternoon
ahead of the convection that will develop in southeast Wyoming
before it heads toward Nebraska after 0z. Nebraska terminals
should expect MVFR conditions during the thunderstorms in the vicinity between 01z-03z
where thunderstorms will be. Overnight, the winds will shift and
possible fog conditions between 08z-12z for ksny could cause IFR
for that terminal. Expect skies to clear up after sunrise due to
mixing in the lower levels of the atmosphere.


Fire weather...
issued at 134 PM MDT Fri Aug 23 2019

With a stalled frontal boundary across the region this afternoon,
can expect convective initiation to continue as showers and
thunderstorms have already formed based off of the kcys radar.
Breezy and dry conditions under threshold levels may be possible
across western Carbon County today though better chances for fire
weather conditions are slated for Saturday and Sunday. Sunday
winds will be stronger gusting up into the mid 40s especially
across Carbon County and relative humidity values in the lower teens will make
for quick fire growth and intensity should any occur. Another cold
front will drop through the region on Monday cooling temperatures
and adding in moisture to raise relative humidity levels and precipitation


Cys watches/warnings/advisories... flag warning from 11 am to 8 PM MDT Saturday for wyz303>305.

Fire Weather Watch from Sunday morning through Sunday evening
for wyz303>305-309-310.

Red flag warning until 8 PM MDT this evening for wyz303-304.




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