322 
FXUS65 KCYS 190548
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
1148 PM MDT Fri Sep 18 2020

.SHORT TERM...(This evening through Saturday)
Issued at 300 PM MDT Fri Sep 18 2020

Currently...A stationary frontal system lays across Wyoming from
Sheridan to Vedauwoo. West of this front afternoon humidity has
fallen to around 10 percent. We're seeing wind gusts in excess of
25 mph across Carbon County this afternoon in FWZ 303 and 304.
Latest hotspot satellite showing the Mullen Wildfire really
heating up this afternoon. Will keep current Red Flag Warnings 
going for this afternoon. Further west...a fairly strong low
pressure system is moving onshore northwestern Oregon. This low
will be the feature to bring strong winds and critical fire
weather conditions to the area tomorrow.

Looks like GFS 700mb winds begin increasing after 12Z Saturday
across Carbon County. Seeing 25 to 35 kts through the early
morning hours Saturday...increasing to 35 to 40kts by afternoon.
Went ahead and upgraded Fire Weather Watch to a Red Flag Warning.

.LONG TERM...(Saturday night through Friday)
Issued at 300 PM MDT Fri Sep 18 2020

Much cooler Saturday night into Sunday as associated cold front
with the low moves through the area. 700mb temperatures fall from
15C Saturday afternoon down to +5C Saturday night. Winds are
expected to stay elevated as the upper low tracks across northern
Wyoming through Sunday. We stay in fairly unsettled west to east
flow through Wednesday...before the upper ridge begins to build
back into the area.

&&

.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1141 PM MDT Fri Sep 18 2020

Haze and smoke will continue to be a problem Saturday resulting 
in reduced visibility around 5 to 6 SM for SE WY terminals. 
Otherwise, VFR conditions are expected at area terminals through 
the forecast period. Winds will pick up Saturday mid-morning with
gusts around 25 to 30 kts west of the Laramie Range ahead of an
approaching cold front.

&&

.FIRE WEATHER...
Issued at 300 PM MDT Fri Sep 18 2020

Critical fire weather conditions ongoing across Carbon County.
Conditions have hit in FWZ 303 and 304...but are struggling for
305 through 307. Given the Mullen Wildfire is really active on
Hotspot satellite...will keep the Red Flag Warnings going through
the rest of the afternoon. Low pressure approaching from the
northwest Saturday will really ramp up winds across southeast
Wyoming. With poor overnight humidity recovery tonight...there
will be an extended period of critical fire weather conditions
Saturday. A Red Flag Warning was issued for FWZ 301 through 310
Saturday for strong winds and low humidity. Could be a period
Saturday afternoon as the low approaches where we may see widely
scattered dry thunderstorms across Carbon County as the front
approaches that could lead to additional fire starts with these
strong winds and low humidity.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Red Flag Warning from 10 AM to 8 PM MDT Saturday for WYZ301>310.

NE...None.
&&

$$

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