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366
FXUS65 KCYS 260954
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
354 AM MDT Sun May 26 2024

.KEY MESSAGES...

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- Strong winds are likely in the wind prone and gap areas of
  southeast Wyoming early this morning through the mid-
  afternoon. Please see the latest High Wind Watch Statement for
  further details.

- A much warmer, milder week ahead as an upper-level ridge
  overtakes the region.
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&&

.SHORT TERM /THROUGH TUESDAY/...
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Issued at 355 AM MDT Sun May 26 2024

Upper ridge axis has shifted east this morning as an upper
trough approaches from the northwest. Shortwave that brought us
the showers and storms Saturday has forced the surface front
well south of Wyoming into southern Colorado and western Kansas.
With the approaching northwest shortwave...Craig to Casper
850/700mb gradients have begun to increase up near 67/44mtrs
respectively. Random Forest wind guidance increasing as
well...showing a 50 percent chance of high winds at Arlington at
09Z and near 60 percent at 15Z. Resulting wind reports in the
Arlington forecast zone have shown increases in wind speeds
with 44 mph reported at Halleck Ridge presently and mid to
upper 30mph gusts elsewhere. Over the Summit...seeing mid to
upper 30 mph gusts. Decided to upgrade the High Wind Watches to
a short fused Wind Warning for WYZ110...116 and 117 this
morning.

Strongest 700/750mb winds on the GFS this morning between 12Z
and 18Z that matches up well with Random Forest high wind
guidance. Winds really begin to decrease after 18Z...down to
40kts at 700mb over the Summit.

As for precip today...best chances look to be across the
northern half of the Panhandle and possibly into
Converse/Niobrara Counties. Thats pretty much what the mesoscale
guidance is showing as this is the area where the main upper
energy from the shortwave moves through the afternoon. By
00Z...upper shortwave forecast to move east into central
Nebraska...with showers ending shortly after 00Z.

Monday continues to show the upper level ridge building to the
west of the CWA. Ridge axis moves into eastern Wyoming Monday
night into Tuesday with dry weather and warmer temperatures.
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&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
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Issued at 355 AM MDT Sun May 26 2024

The medium range to long term forecast includes an active weather
pattern, with mild to summer like temperatures making a return to
the region. There will be an upper level ridge across the Upper
Midwest and Great Lakes region from Wednesday through Saturday. Due
to this blocking mechanism cutting off the mean upper level flow
temporarily, the Intermountain West will have daily afternoon
chances of thunderstorms. The increased chances of thunderstorms
will be from a longwave trough that will not be moving quickly in
the mean upper level H5 flow. At this point of inspection, the
potential for scattered strong thunderstorms exists on each
afternoon from Wednesday to Saturday. Once we have the mean upper
level flow transition from troughing to ridging, the moisture faucet
will a break, and be replaced with much warmer temperatures. Model
guidance is trending towards a much above average daytime high
temperature forecast by next weekend, and into the first week of
June. CPC 8-14 day outlook highlights a below average chance of
moisture, and much above average chance for temperatures favored.
Our first portion of early June in the extended forecast may see
several areas reach the 80s and 90s for daytime highs in the lower
elevations and high plains of the cwa. If model trends continue, we
will see daytime highs 15-25 degrees above average for much of the
forecast area. This would be right on time since 1 June will be the
official start of Meteorological Summer. Stay tuned in the coming
days for weather updates regarding thunderstorm chances, and then
the potential for summer like temperatures to occur.
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&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 929 PM MDT Sat May 25 2024

A weather disturbance aloft will move to the east of the
terminals overnight, with northwest flow aloft developing on
Sunday.

Wyoming TAFS...Scattered to broken clouds from 6000 to
10000 feet will prevail until 00Z, then skies will be clear.
Winds will gust to 38 knots from 15Z to 00Z.

Nebraska TAFS...Scattered to broken clouds from 8000 to
10000 feet will prevail until 00Z, then skies will be clear.
Thunderstorms will be in the vicinity of Chadron and Alliance
from 20Z to 01Z. Winds will gust to 30 knots at Scottsbluff and
Sidney from 15Z to 00Z.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
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WY...High Wind Warning until 3 PM MDT this afternoon for WYZ110-116-
     117.
NE...None.
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&&

$$

SHORT TERM...GCC
LONG TERM...BW
AVIATION...RUBIN