029
FXUS65 KCYS 302001
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
201 PM MDT Thu May 30 2024

.KEY MESSAGES...

- Potential for a late night severe thunderstorm event in the
  Nebraska Panhandle late this evening into the early morning
  hours Friday.

- Daily chances for precipitation continue into the weekend
  before turning drier early next week with above average
  temperatures.

- After a weather disturbance produces a slight chance for
  showers and thunderstorms on Sunday, dry and warm weather will
  prevail for Monday through Thursday.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 200 PM MDT Thu May 30 2024

Beautiful day ongoing this afternoon with only some upper level
clouds being observed across the CWA. Most of Wyoming under the
influence of surface high pressure...in between a departing
cold front across central Nebraska and an approaching cold front
to the northwest. Surface trough extends from north central
Colorado...north into the west slopes of the Laramie Range and
then northwest into northern Carbon County.

Latest mesoscale guidance continuing to forecast a late show
tonight for convection...focusing on thunderstorms developing
after 06Z. HRRR most aggressive with development and coverage
over Cheyenne and Kimball Counties...possibly into the eastern
half of Laramie County. MUCAPE values near 1000 to 1500 J/KG
over these areas this evening. Did add severe wording into the
southern Panhandle for late this evening into early Friday for
thunderstorms.

Upper shortwave tracks across eastern Montana/northeastern
Wyoming Friday afternoon for another rounds of scattered
afternoon and evening showers/thunderstorms.

Saturday may perhaps be our best chance for severe convection as
a dryline develops across southeast Wyoming and pushes eastward
into western Nebraska. Depending on the timing of this dryline
push...could see supercells developing across the Panhandle
Saturday afternoon. Storm Prediction Center already has a Slight
Risk area identified for the Panhandle Saturday afternoon.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Issued at 200 PM MDT Thu May 30 2024

Sunday...A progressive and low amplitude shortwave trough aloft is
progged to move across the forecast area around peak heating.
Although low and mid level moisture looks rather scant, there should
be enough moisture for isolated to widely scattered afternoon
showers and thunderstorms, mainly east of Interstate 25. A bit
warmer than Saturday with 700 mb temperatures near 11 Celsius,
yielding maximum temperatures in the upper 70s west of I-25, with
80s east of I-25.

Monday...Looks like the warmest day of the week with 700 mb
temperatures near 15 Celsius, yielding high temperatures from the
mid 80s to mid 90s. Warm temperatures aloft and limited low and mid
level moisture will likely keep this day dry.

Tuesday...A progressive shortwave trough aloft moves across the
northern Rockies, sending a dry cold front across our counties, and
dropping high temperatures some 5 to 10 degrees.

Wednesday-Thursday...Ridging aloft builds across our forecast area,
producing mostly clear conditions and warm temperatures with 700 mb
temperatures near 14 Celsius on Wednesday and 17 Celsius on
Thursday. Warm temperatures aloft will likely inhibit convective
development.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1134 AM MDT Thu May 30 2024

Westerly flow aloft, combined with a passing cold front and
weather disturbance will help to produce a chance of
thunderstorms mainly after midnight and primarily over the
southern Nebraska Panhandle.

Wyoming TAFS...Clear skies will prevail this afternoon.
Scattered to broken clouds near 15000 feet will occur at Rawlins
overnight and Friday morning. At Laramie, ceilings will lower
from 15000 feet this evening, to 6000 to 10000 feet late tonight
and Friday morning. At Cheyenne, scattered clouds near
12000 feet will occur this evening, then ceilings near
10000 feet will prevail after midnight, lowering to 1500 to
4000 feet early Friday morning. Showers will be in the vicinity
of Cheyenne from 06Z to 11Z. Winds at all terminals will gust to
30 knots until 01Z, and gust to 20 knots at Cheyenne from 06Z
to 11Z, and to 25 knots at Rawlins after 15Z Friday.

Nebraska TAFS...Mostly clear skies will prevail this afternoon,
with scattered clouds near 10000 feet this evening, lowering to
5000 to 10000 feet after 05Z, and to 2500 feet at Sidney after
10Z. Thunderstorms will be in the vicinity of Scottsbluff and
Sidney from 05Z to 15Z, and showers in the vicinity of Chadron
and Alliance after 05Z. Winds will gust to 25 knots at all
terminals until 01Z, and to 22 knots at Scottsbluff from 05Z to
07Z.

&&

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

&&

$$

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