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Area forecast discussion 
National Weather Service Cheyenne Wyoming
556 am MDT Thursday Apr 17 2014

Short term...(today through saturday)
issued at 417 am MDT Thursday Apr 17 2014

Currently...radar showing an area of snow from Glendo to
Bridgeport this morning that lines up pretty well with isentropic
lift at the 300k pressure surface on the GFS. Band is slowly
moving east as the morning progresses and should clear the
Panhandle by sunrise. Our next cold front to move through the area
is just off the Washington state coast early this morning.

Going to be a pretty nice day today as upper level ridging builds
into the area. 700mb temperatures climb from -6c this morning to
+4c tonight. Temperatures should climb into the 60s out in the
Panhandle today with 50s over southeast Wyoming common this afternoon.

700mb winds begin to increase tonight into Friday. GFS forecasting
40kts out over Albany County Friday with a Lee side low developing
over northeastern Wyoming. Going to be windy Friday for much of
the area. Downsloping winds off the Laramie range will really
boost temperatures as well. Did go higher on Friday highs with 80s
possible in the Panhandle. Do believe guidance was a little low
for adjusted up several degrees.

Cold front set to move into southeast Wyoming Friday night into
Saturday. Lifted indices of -2 to -3c Friday evening could produce
some thunderstorms out west of Cheyenne Friday evening into
Saturday ahead of the front.

Long term...(saturday night through wednesday)

Issued at 417 am MDT Thursday Apr 17 2014

Showers and thunderstorms will come to an end Saturday evening as
instability wanes. The surface leeside trough will develop on Sunday as
a shortwave treks across the northern rockies...and will bring
breezy westerly winds to much of the County Warning Area. Some Pacific moisture
will linger in The Rockies on Sunday with a few orographic thunderstorms
possible in the afternoon. Temperatures will warm into the 60s and 70s
for much of the County Warning Area under warm air advection and downslope winds. For Monday...a
low amplitude ridge will move overhead with continued warm and
breezy conditions expected. Available moisture will be slightly
less than on tstorm chances will be less overall but
not out of the question. A stronger shortwave will approach from
the southwest on Tuesday with the main track of this wave looking
to be across western Wyoming on Tuesday night. Models show some
significant differences with the details of this system...but in
general keep the best moisture well to the west with midlevel dry
air moving overhead. A surface low will develop over Montana with the
leeside trough deepening as well. As a result...winds will
strengthen with the developing low and will be out of a southerly
component...likely converging along the Laramie range. Cant rule
out an isolated storm or two especially along and east of the
Laramie range within the strongest low level convergence zone...but
again marginal moisture will keep widespread storms at Bay through
Wednesday morning. Timing of the Pacific front that is expected to
move through the County Warning Area is still very uncertain at this stage due to
large differences with the models in the progression of the upper
trough. Kept some probability of precipitation mainly in the northern and western zones as
these areas will be favored for precipitation chances due to orographics
and proximity to the better moisture. Kept things dry for the most
part further east.


Aviation...(for the 12z tafs through 12z Friday morning)
issued at 555 am MDT Thursday Apr 17 2014

MVFR/IFR conditions in stratus and fog will continue until around
14z for sites across the eastern plains. Winds gusting 25 to 30
kts will the develop late this morning...with southerly winds likely
across the plains and southwest winds expected in the high
country. A brief break in the winds will occur through the late
afternoon and early evening but will become breezy once again
overnight across the Nebraska Panhandle and also near krwl. VFR
conditions will then prevail through Friday.


Fire weather...
issued at 417 am MDT Thursday Apr 17 2014

Warmer temperatures and dry weather for today with increasing
winds tonight into Friday. The next cold front to impact the area
will arrive Friday night into Saturday. Ahead of this
front...winds become strong Friday with afternoon humidities
falling into the upper teens Friday afternoon. Southwest winds
gusting to 40 miles per hour will elevate fire weather conditions for a time
Friday afternoon. As the front moves through the area Friday night
into Saturday...scattered showers and thunderstorms are expected
to develop. Cooler temperatures and increased chances for wetting
rains for Saturday as the front moves through southeast Wyoming.


Cys watches/warnings/advisories...


Short term...claycomb
long term...rjm
fire weather...claycomb