Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 171714
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
1114 AM MDT Thu Oct 17 2019

.SHORT TERM...(Today and tonight)
Issued at 315 AM MDT Thu Oct 17 2019

Strong southwesterly winds today ahead of a strong cold front
moving west to east tonight. Strong winds today will combine with
low afternoon humidities across the boards for dangerous fire
weather for another day. A Red Flag Warning is in place for most
of southeast Wyoming and the northwestern-most portion of the
Nebraska Panhandle 11 am t 7 pm (see the Warning for more details).
Gusts today will be as strong as 40 mph for a good portion of the
High Terrain. Increasing clouds west to east this evening will
indicate the incoming strong cold frontal passage set to occur
this Avignon and into Friday. The front will bring a limited
amount of precipitation (rain at the lower elevations and snow at
the highest elevations) along with a slight chance of
thunderstorms during daylight hours as guidance show a limited
amount of instability. Warm temperatures again prevail today
under the southwesterly flow.

.LONG TERM...(Friday through Wednesday)
Issued at 315 AM MDT Thu Oct 17 2019

Colder air will filter in behind the Thursday/Friday cold front,
with high temperatures coming down to near normal for this time of
year. Winds will continue to be strong through the period as they
turn west under a branch of the jet stream aloft. This may create
wind impacts across our more wind-prone areas during the day
Friday. A High Wind Watch has already been issued for the
Arlington area, with gusts to 60 mph possible. The Watch may need
to be expanded east to the southern Laramie Range foothills as
winds align vertically out of the west with 700 mb winds near 60
mph.

Another shot at precipitation, this time more widespread, as well
as high wind headlines Sunday and into the beginning of next week
as another upper level disturbance pushes through the area,
accompanied by a strong upper level jet. 300 mb winds on Sunday
will be near 70 mph with the ability to effect the wind-prone
areas of southeast Wyoming. By Monday however, 300 mb winds of 125
mph will sit over southeast Wyoming and the western Nebraska
Panhandle for most of the day with breezy conditions expected
across the region, and High Wind headlines for most wind-prone
sites in southeast Wyoming. This disturbance will have the
capability of bringing snow to the lower elevations Sunday and
Monday as below normal temperatures are ushered into the region
with another strong cold frontal passage early Sunday morning. The
closed low that accompanies this system indicates strong
instability with this system as cold air pools aloft, and
instability parameters become heightened. Thundersnow will likely
be widespread.

The active pattern continues into mid-week with indications that
another upper level disturbance will move into the HIgh Plains and
adjacent mountains late Wednesday.

&&

.AVIATION...(For the 18Z TAFS through 18Z Friday morning)
Issued at 1114 AM MDT Thu Oct 17 2019

VFR conditions expected through the period for all terminals with
just some high clouds passing across.  Some gusty westerly winds
this afternoon mainly affecting KRWL and KLAR.  Sfc cold front will
move east across the area later tonight switching winds out of the
west to nw.

&&

.FIRE WEATHER...
Issued at 315 AM MDT Thu Oct 17 2019

Poor overnight recoveries will give way to low afternoon
humidities. Low humidities will combine with gusts to 40 mph
across southeast Wyoming and gusts to 25 mph across the
northwestern Panhandle for a dangerous fire weather day. Haines of
5 will be relatively widespread across the High Plains and High
Terrain. Pattern change expected beginning tonight and Friday as
cooler air filters in behind a strong cold front and the chance
for high elevation precipitation. More widespread precipitation
Saturday night and Sunday.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Red Flag Warning until 7 PM MDT this evening for WYZ301>309.

     High Wind Watch from Friday morning through Friday afternoon for
     WYZ110.

NE...Red Flag Warning until 7 PM MDT this evening for NEZ311.

&&

$$

SHORT TERM...AB
LONG TERM...AB
AVIATION...RE
FIRE WEATHER...AB


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