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Area forecast discussion 
National Weather Service Cheyenne Wyoming
438 am MST Thursday Nov 26 2015

Short term...(today through Friday night)
issued at 300 am MST Thursday Nov 26 2015

Snow amounts and possibility of more freezing precipitation the forecast
challenges in the short term.

Currently...surface cold front currently down over northwestern
Colorado this morning. Northeast low levels winds and temperatures
now in the low teens up by Douglas and Rawlins and low 20s in the
Panhandle. Not seeing the cooling cloud tops we would like to see
for widespread heavy snow so far this morning. Infrared imagery showing
the coldest cloud tops up in rivertons area so far. There is an
upper shortwave seen though on water vapor imagery over southern
Utah moving our way. Thinking is this will be the upper level
support to get more widespread snow development later this
morning. For now...will let current headlines go as is and
continue monitoring conditions.

Cheyenne did pick up a quick inch of snow since it turned over
around midnight. As cold as the temperatures are this
morning...snow ratios are going to be very despite lack
of upper level support...thinking we are still going to see some
impressive snow totals. Especially across northern Carbon and
western Converse counties where the warnings are in effect.

European model (ecmwf) and GFS bring upper low into extreme southwest
Wyoming/northeast Utah by 18z with quantitative precipitation forecast band currently over
rivertons area shifting east. Energy continues to impact our County warning forecast area
through at east 06z extending the headlines was a
good call by the day shift yesterday.

GFS soundings showing a return of possible freezing rain/drizzle
to areas east of the Laramie range Friday. Did introduce freezing
drizzle back into the forecast for much of Friday morning into the
afternoon basically from Cheyenne to Scottsbluff and points south.

Need to thinking of windchill headlines for late tonight into
Friday as well. Getting too warm of temperatures from guidance for
tonight/Friday with 700mb temperatures of -14 to -15c. Especially
out by Rawlins and Laramie. Dropped min temperatures out there by
10 degrees and we may need to cool them even further. Getting
windchill temperatures approaching -25f for Friday morning out
that way. Colder temperatures would give US even lower windchills.
GFS 700mb winds at 30kts out that windy conditions look
to continue as well.

Long term...(saturday through wednesday)
issued at 300 am MST Thursday Nov 26 2015 lobe of energy from the upper low will rotate
northeast across our counties...producing areas of light snow...with
greatest areal coverage over our western counties. Continued cold
with cloud cover and cold air aloft.

Sunday...cold upper trough rotates across northern Wyoming and
Montana with cold air aloft over our counties helping isolated snow
showers to develop in the unstable airmass aloft.

Monday...less coverage of snow showers as the low and middle levels dry
out with the upper low moving to our east.

Tuesday...decent warming trend finally begins as the ridge aloft
moves nearby and shallow cold air retreats to our east...though
still not as warm due to north flow aloft.

Wednesday...warming trend continues as the flow aloft weakens with
ridging to our southwest.


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 430 am MST Thursday Nov 26 2015

Mountains obscured.

Wyoming tafs...occasional IFR at Rawlins until 16z...then MVFR
through 02z...then VFR. IFR at Laramie and Cheyenne...becoming
MVFR this afternoon and mostly MVFR tonight.

Nebraska tafs...improving to MVFR at Chadron and Scottsbluff
by this afternoon...and occasional VFR tonight. Mostly IFR at
Sidney...with localized MVFR from 16z to 02z.


Fire weather...
issued at 300 am MST Thursday Nov 26 2015

No fire weather concerns anticipated in the near term due to snow
through the end of the week...and very cold temperatures through the


Cys watches/warnings/advisories...
Wyoming...Winter Weather Advisory until 5 PM MST this afternoon for wyz102.

Winter Storm Warning until midnight MST tonight for wyz103>105-

Winter Weather Advisory until midnight MST tonight for

Winter Storm Warning until 5 PM MST this afternoon for wyz101.

NE...Winter Weather Advisory until 5 PM MST this afternoon for



Short term...gcc
long term...Rubin
fire weather...gcc

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