Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 081730

Area Forecast Discussion
National Weather Service Cheyenne WY
1030 AM MST Fri Dec 8 2017

.SHORT TERM...(Today through Sunday)
Issued at 235 AM MST Fri Dec 8 2017

Not much change in the forecast in the short term. High pressure
stationary over the west coast blocking any systems from the
Pacific to move on shore.

Am concerned with the winds. GFS 850/700mb winds quite strong
across the eastern portion of the CWFA. Will see breezy conditions
for the Panhandle over to the east slopes of the Laramie Range.
GFS forecasting 40-45kt 850mb winds over the Panhandle this
afternoon that could push us close to warning criteria. Decided to
hold off on any wind headlines. Day shift will need to monitor
wind speeds though through the day.

Fire weather wise...think afternoon humidity will stay above
critical levels with upper teens and low 20 percent today and
Saturday. But Sunday may need a headline as humidity gets pretty

.LONG TERM...(Sunday night through Thursday)
Issued at 235 AM MST Fri Dec 8 2017

Next week will feature above normal temperatures (normal highs
this time of year are in the 30s) and continued dry conditions.
Pattern will remain largely unchanged from the short-term period,
with a highly amplified ridge of high pressure situated across the
west coast, with a deep trough of low pressure across the Great
Lakes and eastern U.S. Tuesday looks to be the warmest day as
highs warm into the 40s west of the Laramie Range and 50s to near
60s on the eastern plains. Although high winds are not seen at
this time, the typically breezy afternoons are expected with gusts
in the 25-35 mph range. Even looking beyond this period, no
significant cold snaps are seen on the horizon.


.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1025 AM MST Fri Dec 8 2017

Latest surface analysis was showing a very tight pressure gradient
between northern Colorado and the Nebraska panhandle. This
gradient is expected to gradually weaken this afternoon. However,
wind gusts will range from 35 to 45 kts over KCYS with 30 to 40 kt
gusts possible over the southern Nebraska Panhandle. These wind
speeds will diminish this evening as the upper level ridge
continues to build over the region. &&

Issued at 245 AM MST Fri Dec 8 2017

High pressure over the west coast blocking any Pacific storm
systems from moving into the area. Expect mostly sunny skies and
breezy north to northwest winds each day. Slowly warming
temperatures with afternoon humidity falling into the upper teens
and low 20 percent range. Dry day Sunday for areas east of the
Laramie Range could lead to elevated to locally critical fire
weather conditions as afternoon humidity falls to the low to mid


WY...High Wind Warning until 5 PM MST this afternoon for WYZ116>119.



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