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419
FXUS65 KCYS 180611
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
1202 AM MDT Sun Aug 18 2019

.UPDATE...
Issued at 808 PM MDT Sat Aug 17 2019

Humidity is slowly receovering this evening with most reporting
sites above critical values. Have therefore allowed the Red Flag
Warning to expire on time this evening. Critical fire weather
conditions expected to return Sunday with Red Flag Warnings in
effect from noon to 8 PM.

UPDATE Issued at 527 PM MDT Sat Aug 17 2019

...Please see latest 0Z aviation discussion...

UPDATE Issued at 356 PM MDT Sat Aug 17 2019

Dry and breezy conditions expected to continue Sunday for FWZ
310...especially the southwest part of the zone. Cheyenne to
Wheatland should experience these conditions...so decided to
upgrade the watch to a Red Flag Warning. Updates have been sent.

&&

.SHORT TERM...(This evening through Monday)
Issued at 225 PM MDT Sat Aug 17 2019

Isolated showers and a few storms moving east across mainly far
southern parts of the CWA attm. Little rain likely falling from
these with a rather dry sub-cloud layer. Expect these to
dissipate this evening with diurnal cooling. Overnight a cool
front will sag south across the area and should produce some low
stratus for a time later tonight into Sunday morning over the
plains. The front will bank up against the mtns early Sunday then
some question as how fast it will move back east. A little cooler
over the plains Sunday then very warm conditions return Monday.

.LONG TERM...(Monday night through Saturday)
Issued at 225 PM MDT Sat Aug 17 2019

Chances for showers and tstms look to return beginning Tuesday
with the best chances looking to be late Tuesday through Weds as a
push of cooler air drops down the plains and banks up against the
mtns creating some upslope flow. A little cooler as well Tuesday
and Weds. Drier air then returns late week reducing convection to
a more isolated basis Thursday, with dry weather Friday and
Saturday.

&&

.AVIATION...(For the 06Z TAFS through Sunday evening)
Issued at 1202 AM MDT Sun Aug 18 2019

A surface cold front has pushed southward across the eastern plains
late this evening, resulting in lower CIGS and a slight potential
for fog through 12z.  Expect KLAR and KRWL to remain VFR through the
night since the front will likely not make it that far west. Further
east, expect at least MVFR to near IFR CIGS for most terminals. Fog
is more likely at KBFF and KCYS through 12z Sunday, but even those
sites are low confidence at this time, at least for persist fog
through the night. Any low CIGS and fog will lift by 15z, with dry
conditions through Sunday evening.

&&

.FIRE WEATHER...
Issued at 225 PM MDT Sat Aug 17 2019

Dry and very warm conditions will persist over the districts
through Monday before a trend to a little cooler conditions and
better chances for rain arrive by midweek. Critical fire weather
conditions will persist over parts of southeast Wyoming into this
evening and is likely Sunday afternoon and evening mainly out
west as winds will be gusty again. Conditions are expected to ease
Monday onward.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...

WY...Red Flag Warning from noon to 8 PM MDT Sunday for
WYZ303-304-310.

NE...None.
&&

$$

UPDATE...GCC
SHORT TERM...RE
LONG TERM...RE
AVIATION...TJT
FIRE WEATHER...RE