Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 300953

Area Forecast Discussion
National Weather Service Cheyenne WY
253 AM MST Wed Nov 30 2016

.SHORT TERM...(Today through Friday)
Issued at 230 AM MST Wed Nov 30 2016

No change in the overall synoptic weather pattern over the last 24
hours w/ a large and vigorous low pressure system remaining nearly
stationary over central Minnesota. Gusty winds continue early this
morning over eastern Wyoming and the western Nebraska Panhandle w/
strong pressure W-E pressure gradients in place. Periodic shots of
wrap-around moisture are still resulting in areas of snow over the
northern Nebraska Panhandle. Do not expect to see any accumulation
from this activity. The upper low should finally shift eastward to
the western Great Lakes by 00z this evening with a weak short-wave
ridge briefly ending snow chances by mid/late afternoon. Expect to
see one more breezy day today given a strong MSLP gradient and the
continued presence of 25 to 35 knot flow aloft. Precipitation will
increase again after 12z Thursday with good mid-level PVA ahead of
the next disturbance. Highest PoPs should remain confined to areas
along and west of the Laramie Range through Friday. Overall we are
looking at a cold and unsettled weather pattern, but chances for a
high-impact weather event appear nil for a few days. Overnight low
temperatures will average in the teens/single digits, coldest over
our western zones.

.LONG TERM...(Friday night through Tuesday)
Issued at 230 AM MST Wed Nov 30 2016

Very cold in the long term, probably the coldest air of the season
so far moving into the area.

Starting off Friday night, shortwave passing south across Colorado
with 700mb temperatures around -12C. Single digit lows out west
with teens forecast east.

Going to see an increase in winds Sunday as GFS 700mb winds climb
to 40kts across Carbon County. This may help moderate temperatures
some. 700mb temperatures only rise to around -6C Sunday
afternoon. Sunday will most likely be our warmest day in the
extended with 40s out in the Panhandle and 30s west of the Laramie

Stronger Pacific system still on track for Monday/Tuesday and we
will certainly need to watch the exact track. Some run to run
inconsistencies with the track. Latest guidance now has heavier
snow across Colorado where previous run had the bulk of the snow
over Wyoming.

Certainly going to get colder next week. Both the GFS and ECMWF
are forecasting 700mb temperatures down to -20C and 850mb
temperatures of -8 to -12C. Could see the seasons first below zero
mins with highs only in the low teens for Tuesday should this
solution pan out. Did undercut guidance temperatures for Tuesday.
May need to cut more if guidance continues to show these cold
700mb temperatures.


.AVIATION...(For the 06Z TAFS through Wednesday evening)

Low CIGS across western NE will gradually lift tonight and early
Wednesday morning as the storm system across the northern plains
slowly moves eastward. Strong northwest winds gusting between 30-40
kts will likely continue through tonight across the High Plains.
Winds will slowly subside by sunrise Wednesday...especially further
west...but will gradually increase by late Wednesday morning across
the area.


Issued at 104 AM MST Wed Nov 30 2016

No concerns. A cool and unsettled weather pattern will support RHs
well outside of critical thresholds. Today will be quite breezy w/
wind gusts over 35 MPH along/east of the Laramie Range. Decreasing
winds can be expected after today.




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