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Area forecast discussion 
National Weather Service Cheyenne Wyoming
621 PM MST Monday Dec 22 2014

issued at 621 PM MST Monday Dec 22 2014

Winds have decreased early this evening across the
let the Wind Advisory expire. Still expect an increase of winds
through the later evening hours though...with high wind warnings
going into effect at 8 PM for the southern Panhandle and most
locations across the Wyo plains. Do think there will some light
snow accumulations overnight along with the strong winds...with
locally reduced visibilities and slick roads possible across this
area. A Winter Storm Warning will also go into effect at 8 PM for
the northern half of the Nebraska Panhandle due to expected
combination of more widespread heavier snow and strong winds. In
addition...bumped up probability of precipitation and snow totals slightly along the
Laramie range and nearby foothills for this evening as light to
moderate snow bands continue to move through this area as of 6 PM.


Short term...(this evening through wednesday)
issued at 245 PM MST Monday Dec 22 2014

Another challenging forecast with winds and accumulating
snow/blowing snow being the forecast challenges in the short term.

Currently...pretty tranquil early this afternoon. Gusty northwest
winds being seen on area metars. Winds just under advisory levels
at Sidney and Chadron. Still have a couple hours of possible will keep the advisory going out in the Panhandle for
this afternoon. Latest surface analysis showing a cold front over
the western Dakotas this afternoon.

For tonight...upper low closes off as forecast over eastern
Nebraska. Short range guidance continues to show energy coming
around the north side of the low into the northern Panhandle
tonight. At the same time...850/700mb winds increase dramatically
east of the Laramie range. 850mb winds increase to 40kts just
north of the County warning forecast area in Campbell and Weston counties with 700mb winds
increasing to over 65kts. Looking at NAM BUFKIT soundings...winds
are quite strong at the top of the mixing layer...on the order of
60-65kts. Energy around the back side of the low moves into the
northern Panhandle late this evening with a pretty good signal for
moderate snow along the Pine Ridge in Dawes and Sioux County.
Combination of 3-5 inches of snow along with wind gusts to
40-45mph look likely across this area. Decided to issue a short
fused Winter Storm Warning for the northern Panhandle. Evening
shift may need to expand this west into Niobrara County based on
radar trends/reports. Went ahead and upgraded the high wind watch
to a warning for the remainder of the County warning forecast area east of the Laramie
range. Strongest winds look to occur between the 06z and 12z

Winds ease Tuesday as upper low continue to move east. Area dries
out completely by 18z. Should be able to drop all headlines by
Tuesday morning.

Long term...(wednesday night through monday)
issued at 245 PM MST Monday Dec 22 2014

Next upper system to affect the regional weather will make its
approach Christmas day with some snow probably spreading into
western parts of the County Warning Area during the afternoon. GFS just a bit
faster than the latest ec but not significantly different. Snow
should move across the County Warning Area Thursday night and come to an end
Friday morning as the upper trough axis passes across. Relatively
fast movement of the system should keep snowfall amounts down but
2-4 inches over lower elevations looks a decent bet at this time.
Secondary weaker shortwave drops southeast across the area Friday
night but this should only bring some snow showers mainly to the
mountains progressive pattern continues with a short upper ridge
passing across late Saturday with dry weather. Next surge of cold
air arrives early Monday ahead of next large upper trough digging
across the western part of the country with snow likely returning


Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 621 PM MST Monday Dec 22 2014

Continue to anticipate strong winds and snow to develop later this
evening across much of the area. Looking at IFR conditions in snow
and blowing snow across the Wyo and Nebraska plains
overnight...with MVFR conditions in the high valleys out west. The
mountains will remain obscured as well. Conditions will slowly
improve from west to east Tuesday morning...however winds will
remain strong through the day. Gusts of 35 to 45 kts are likely
across the plains...with 30 to 35 kts out west.


Fire weather...
issued at 245 PM MST Monday Dec 22 2014

No critical fire weather over the next few days. Mountain snow will
continue through Tuesday with 2 to 4 feet of total snow accumulation
in the snowy's and Sierra madres. Windy conditions are expected east
of the Laramie range today...with stronger winds possible late this
evening through Tuesday morning. A Wind Advisory and high wind watch
have been issued for parts of the area. Light snowfall accumulations
are expected over the plains tonight.


Cys watches/warnings/advisories...
Wyoming...High Wind Warning until 11 am MST Tuesday for wyz101-102-107-108-

Winter Storm Warning until 5 am MST Tuesday for wyz112-114.

NE...Winter Storm Warning until 11 am MST Tuesday for nez002-003-095-

High Wind Warning until 11 am MST Tuesday for nez019>021-054-055.



short term...gcc
fire weather...gcc

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