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fxus65 kcys 172022 
afdcys

Area forecast discussion
National Weather Service Cheyenne Wyoming
222 PM MDT Tue Sep 17 2019

Short term...(this evening through wednesday)
issued at 230 PM MDT Tue Sep 17 2019

Forecast concerns deal with winds and severe thunderstorm
possibility today.

Currently...surface front beginning to push into western Carbon
County early this afternoon. Upper level low seen on water vapor
imagery can be seen over extreme southeastern Idaho into
northwestern Wyoming. On radar...we are seeing a line of mainly
showers ahead of the front from Casper to just west of Laramie. We
have seen some pretty good wind gusts out of these showers. Had 69
mph reported at Halleck Ridge and 58 mph at Dana Ridge wydot
sites. Further southwest...still getting reports out of the Camp
Creek RAWS site in southwest Carbon County of 50-55mph.

Winds look to ease this evening as the front moves through the
southern Panhandle by 03z. Still elevated overnight with GFS
showing 35-40kts across southeast Wyoming.

Long term...(wednesday night through tuesday)
issued at 230 PM MDT Tue Sep 17 2019

Breezy conditions Wednesday and Thursday as 700mb winds stay up in
the 30-35kt range. Winds increase Thursday afternoon with the
approach of our next Pacific low pressure system. Could see better
chances for non-convective winds as Craig to Casper gradients
approach 60mtrs at 850mbs. Upper low center slighter more south
than todays low...so maybe a more widespread coverage of showers
possible. Snow still possible in the snowy and Sierra Madre ranges
as 700mb temperatures forecast below freezing.

Warmer and drier for the weekend into next week as ridge builds
into the area. Temperatures at 700mb climb back to near +10c by
Monday.

&&

Aviation...(for the 18z tafs through 18z Wednesday morning)
issued at 1145 am MDT Tue Sep 17 2019

Strong low to mid-level southwest winds across southeast Wyoming
and the Nebraska Panhandle will be the main hazard for the next 12
hours or so. Turbulence and wind shear near the ground will be
possible at the terminals this afternoon. Klar and krwl terminals
will likely exceed 40-45 knots for wind gusts this afternoon. The
primary timeframe for these terminals to experience the strong
winds will be from 17/18z-00z. Kcys does have the possibility of
experiencing wind gusts up to 35 knots between 17/18z-00z as
well. The Panhandle will see winds increase up to 25-30 knots
during the 17 /18z-03z time period. Winds will decrease in peak
intensity the further south in the Panhandle aircrafts travel,
especially towards ksny.

In addition the wind hazards for today, vcsh/shra/tsra will
continue to develop and move north and east across Wyoming into
portions of the Panhandle. The initial focus will be over Carbon
County. From there the rain showers will move over Platte,
Converse, and Niobrara counties. Wind gusts could reach up to 60
knots in local areas with the wind plus storm winds factored in.
All vcsh/shra/tsra activity will decrease west to east from
17/00z-18/02z as winds decrease slowly as well. Occasional
overnight gusts are possible at the Nebraska terminal sites up to
15-20 knots and are mentioned in the tafs.

&&

Fire weather...
issued at 230 PM MDT Tue Sep 17 2019

Windy conditions continue this afternoon as a front moves through
the area. Associated low pressure system tracking across southern
Montana and northern Wyoming is a very classic wind producer for
this area. Look for winds to begin easing slightly this
evening...but westerly winds gusting to 30 mph likely all night.
Breezy conditions expected Wednesday and Thursday with near
critical afternoon humidity as temperatures begin to rebound.
Could get close to critical fire weather conditions Wednesday
afternoon across fwz 303...northern Carbon County and again on
Thursday. Winds begin to increase again Thursday as another low
pressure system approaches from the west. Wetting rains possible
Friday.

&&

Cys watches/warnings/advisories...
Wyoming...High Wind Warning until 6 PM MDT this evening for wyz104-109>111.

NE...none.
&&

$$

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