Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 230850

Area Forecast Discussion
National Weather Service Cheyenne WY
250 AM MDT Sun Oct 23 2016

.SHORT TERM...(Today through Tuesday)
Issued at 151 AM MDT Sun Oct 23 2016

The cold front is mostly through the forecast area early this
morning. Winds behind the front are out of the north-northeast and
will turn to the south-southeast by mid-morning across the plains.
Winds out west in the high country should pick up and veer to the
southwest through the late morning as the front shifts east a bit
into the plains. Temperatures will be cooler today and moisture
higher tho, so fire weather concerns should remain minimal. Not
anticipating much movement from the front through Monday morning
until the train of upper level shortwaves moves up from the

Monday will be warmer as the thermal ridge moves overhead in
southwest flow aloft. The sfc front will push east into the
panhandle by the afternoon with winds becoming quite breezy along
and west of the I-25 as it does so. Downslope drying may bring
humidities down into the upper teens across the Wyoming plains,
but winds here are looking to be minimal at this point. Increasing
Pacific moisture from the southwest will bring showers and perhaps
an isolated t-storm or two to the high country on Monday as well.
For Tuesday, flow aloft shifts back to the west-southwest with the
nose of the jet core impinging on the western slopes. The stronger
shortwave energy passes over the Rockies late Tuesday morning so
the best chance for showers may late morning-early afternoon and
mainly across southeast Wyoming. However, with strengthening winds
aloft, may see orographic showers persist later in the day as

.LONG TERM...(Tuesday night through Saturday)
Issued at 245 AM MDT Sun Oct 23 2016

Medium range models in reasonable agreement next week...and
generally show dry conditions continuing through the last week of
October with mild temperatures. Pacific upper level trough will
move east of the area Tuesday night and early Wednesday with a
continuation of mild temperatures for Wednesday afternoon as
another upper ridge builds northward west of the continental
divide. Models continue to show 700mb temperatures climbing
between 6c to 10c for Thursday and Friday as the ridge axis moves
over the forecast area...which translates to highs in the 70`s
across most of the forecast area...with areas like
Saratoga...Laramie...and Rawlins west of I-25 a bit cooler and
generally in the mid to upper 60`s. The lowest elevations across
the western Nebraska panhandle and locations near the NE border
may see highs in the low 80`s. By late Friday...the ECMWF shows
the next Pacific upper level trough moving into Wyoming with Rain
showers mainly over the mountains and adjacent valleys...while
the other 00z models show another ridge building to the west of
the forecast area with little evidence of any disturbance aloft
embedded in the westerly flow. Ensembles show a wide variety of did not change day 6 and 7 much with a continuation
of mild temperatures and generally dry conditions.


.AVIATION...(For the 12Z TAFS through Sunday night)
Issued at 230 AM MDT Sun Oct 23 2016

VFR conditions will prevail through this evening with scattered
coverage high clouds around 20k to 25k feet AGL. Winds are
expected to be light for all terminals this morning becoming
gusty once again over southeast Wyoming this afternoon...but not
as strong as Saturday. Wind gusts around 25 knots are possible at
KLAR and KRWL this afternoon.


Issued at 151 AM MDT Sun Oct 23 2016

Winds across Carbon County will become breezy today with gusts as
high as 30 mph. The lowest humidities in the high valleys should
only drop into the upper teens to low 20s. Higher moisture values
will be present across the plains behind the cold front, so fire
weather concerns will be minimal. Breezy winds look to spread a
bit further east to include locations along I-25 on Monday, but
humidity values should remain 20 percent or higher within the area
of breeziest winds. Chances for precipitation will increase on
Monday in the high country, continuing through Tuesday.




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