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000
FXUS65 KCYS 172012
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
212 PM MDT Wed Apr 17 2024

.KEY MESSAGES...

- A cold front will bring cold and unsettled weather for
  Thursday through Saturday, along with a chance for rain and
  snow showers.

- Much warmer temperatures are expected for Sunday through
  Wednesday.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 212 PM MDT Wed Apr 17 2024

Tonight...Quite a contrast in temperatures on either side of the
slowly advancing cold front moving southward across our counties. At
early afternoon, the cold front had moved into Platte and Goshen
Counties of Wyoming, with temperatures only in the upper 30s at
Douglas and Wheatland, while temperatures were in the upper 50s to
lower 60s from Cheyenne to Sidney. Frontal lift and forcing will
help scattered to numerous rain and snow showers, and possibly a
few thunderstorms, to develop along and after the frontal
passage, with decreasing areal coverage after midnight as lift
wanes. Based on the boundary layer progs, areas of fog look like
a decent bet across much of Albany, Platte and Laramie Counties
after midnight.

Thursday...Considerably colder in the wake of the cold front and
with widespread low clouds persisting much of the day. Some showers
in the morning expected to end in the afternoon with limited lift.
Maximum temperatures only in the 40s to lower 50s, with 700 mb
temperatures near -9 Celsius.

Thursday night...Looks like the front will stall across our southern
counties, which should act as a focus for scattered snow shower
development from Laramie to Cheyenne and to Sidney.

Friday...Cyclonic flow aloft and relatively deep upslope winds will
lift the moist airmass and continue to produce scattered rain
and snow showers across our southern counties from the Snowy Range
eastward to Cheyenne and to Sidney. Continued cold with maximum
temperatures only in the upper 30s to mid 40s with 700 mb
temperatures near -9 Celsius, and temperatures could even be colder
if low clouds remain widespread.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Issued at 212 PM MDT Wed Apr 17 2024

Friday night/Saturday...Scattered to numerous snow showers look
to continue across our southern counties in deep, moist upslope
flow and with a shortwave trough moving overhead. Difficult to
say how much snowfall accumulation we could see especially with
temperatures likely in the 40s during the day on Saturday,
through we could see 1 to 3 inches of snow Friday night from
Laramie to Cheyenne to Sidney.

Sunday...Quite a quick warming trend is expected as the cold airmass
is scoured out under northwest flow aloft with maximum temperatures
some 20 to 25 degrees warmer than those of Saturday as a surface lee
trough becomes established across eastern Wyoming.

Monday-Wednesday...Primarily zonal flow aloft prevails with ridging
aloft building by Wednesday, helping high temperatures to climb into
the 60s at most locations for Monday and Tuesday, with mainly 70s
for Wednesday. Convective parameters indicate showers possible for
Wednesday afternoon.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1123 AM MDT Wed Apr 17 2024

Showers will remain scattered throughout the afternoon in
southeast Wyoming and western Nebraska although rain will not
reduce VIS at any terminals to below MVFR levels. A cold front
will move southward through the high plains, reaching CYS around
23z. This will bring a northerly wind shift as well as low
ceilings to most areas east of I-25. MVFR is likely at CYS with
IFR possible after 2z if moisture is more pronounced in the
lower levels.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.

&&

$$

SHORT TERM...RUBIN
LONG TERM...RUBIN
AVIATION...MAC