Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 090855 CCA
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
222 AM MDT Sun Aug 9 2020

.SHORT TERM...(Today and tonight)
Issued at 230 AM MDT Sun Aug 9 2020

Fire weather concerns are the challenge with this forecast
package.

Currently...Pesky cold front remains over the area this morning
from just north of Chadron to Douglas to Saratoga. Another cold
front analyzed over western Montana into southwestern Idaho. Still
seeing 50 Tds in the Panhandle with teens and low 20 TD west of
the front across Carbon County this morning. 2 AM humidity
recoveries very poor across Carbon County with 10 to 15 percent
being reported on several WYDOT sensors. Rawlins reporting 33
percent at 2 AM...Laramie at 31 percent.

These poor RH recoveries are going to start off a critical fire
weather day for much of southeast Wyoming. GFS continues to show
soundings mixing down 25-30kts of winds across Carbon and Albany
Counties...so previous Red Flag Warning looking pretty good. Did add
the Laramie Range into the RFW for today. They did hit yesterday
with lesser wind than today...so thought it prudent to add.

As for thunderstorms this afternoon...it looks like bulk of the
storms will be in North Platte`s area today. Not too concerned
with severe storms this afternoon/evening...but did add some
chicken 15 PoPs into the Panhandle to account for any stray
storms. Mesoscale guidance does show a few storms after 22Z today.

Front over Montana forecast to settle into the area this evening
with higher humidity behind it for our eastern zones. Out
west...poor humidity recoveries expected once again as winds stay
elevated.

.LONG TERM...(Monday through Saturday)
Issued at 230 AM MDT Sun Aug 9 2020

Carbon County stays west of the front for Monday and Tuesday. GFS
700mb winds stay strong from the west both days. Likely going to
see Red Flag conditions both days across Carbon and parts of
Albany County both days. Added a Fire Weather Watch for FWZs 303
through 308 for Monday.

See an eastward surge of that front Tuesday with the much drier
air surging east...so zones east of the Laramie Range could be
looking at Red Flag conditions Tuesday. Likely to see Red Flag
Warnings on a daily basis for various parts of the CWA through the
upcoming week.


&&

.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1131 PM MDT Sat Aug 8 2020

The last remaining TSRA/SHRA is departing the KCDR area at this
hour after an active TSRA day in the central and north NE
Panhandle.

Much less concern for TSRA/SHRA through the next 24 hours with
only very isolated SHRA in the southern NE Panhandle possibly near
KSNY from 22-01Z this afternoon to early evening. Confidence
remains low of vicinity for KSNY so have left out of current TAF
cycle for now. Surface winds will be light from the south for the
NE sites and more westerly for the WY sites overnight. Winds will
generally shift out of the north Sunday with a weak front passing
through the region. VFR is expected through the TAF period.

&&

.FIRE WEATHER...
Issued at 230 AM MDT Sun Aug 9 2020

A cold front approaching the area from the north today will
increase winds over our western fire weather zones by mid morning
through the afternoon. Red Flag Warnings are in effect for FWZs
302 through 309 from 9 AM through 8PM. Front stalls along the east
slopes of the Laramie Range through Monday before shifting
eastward Tuesday and Wednesday. West of the front...gusty west
winds and very dry air remains in place for critical fire weather
conditions again Monday and possibly beyond. A Fire Weather Watch
is in effect for Monday for FWZs 303 through 308. As front moves
east into central Nebraska Tuesday...the very dry air shifts east
of the Laramie Range...resulting in possible critical fire weather
conditions into the Nebraska Panhandle Tuesday afternoon.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Red Flag Warning from 9 AM this morning to 8 PM MDT this evening
     for WYZ302>309.

     Fire Weather Watch from Monday morning through Monday evening
     for WYZ303>308.

NE...None.
&&

$$

SHORT TERM...GCC
LONG TERM...GCC
AVIATION...JSA
FIRE WEATHER...GCC


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