846
FXUS63 KUNR 301633
AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
1033 AM MDT Thu May 30 2024

.KEY MESSAGES...

- Cooler and unsettled at times late this week.

- Warm weather for this weekend and beyond, with a drier pattern
  likely developing for much of next week.

&&

.DISCUSSION...(Today Through Wednesday)
Issued at 245 AM MDT Thu May 30 2024

Current surface analysis shows low pressure over northwest SD,
with a cold front pushing through western SD and the NE panhandle.
Upper level analysis has trough located across the northern and
central Rockies, with energy out ahead of it across much of the
Plains. Main piece of energy has shifted north and east of the
forecast area, with secondary wave moving across western SD in
vicinity of the front. KUDX radar shows scattered to numerous
showers and thunderstorms from far northeast WY to much of western
and central SD, with more isolated activity from southern
portions of northeast WY into southwest SD. Temps are mostly in
the 50s with west-northwest winds behind the front, mostly from
the south ahead of it.

Upper trough to the west will only slowly track east over the next
couple of days, with at least a couple more disturbances within it
tracking across the northern Plains through Friday night. Showers
and storms with the current disturbance will continue to track east-
northeast across the area through the mid to late morning hours with
the cold front. Highs today will range from the upper 50s/lower 60s
across northeast WY and the Black Hills to the lower 70s toward
south central SD, with breezy northwesterly winds across northwest
into west central SD. Additional showers and storms will redevelop
along the nearly stalled out front from eastern SD to central NE
this afternoon. A few showers and storms could redevelop across far
south central SD in the afternoon, in closer vicinity to the front,
but much of the activity and stronger storm potential is expected to
be east of the forecast area. Farther west, there is likely to be a
break in shower activity from later this morning into tonight.
However, the next disturbance pushing through the trough should
bring increasing chances for showers later tonight and Friday. A few
storms will likely develop across at least southern SD. The threat
for severe storms looks low at this point, but forecast MLCAPE to
around 500 j/kg and modest shear over southwest/south central SD
later Friday into Friday evening would support some potential for a
strong storm or two. Highs on Friday will still be on the cooler
side, mostly 60s and lower 70s.

The main upper trough finally shifts east of the region Friday
night/early Saturday, with relatively flat ridge developing over the
Rockies on Saturday. This will lead to warmer temps over the
weekend, with highs back in the 70s and 80s, warmest on Sunday.
Saturday looks to be the drier day over the weekend, but cannot rule
out some chances for showers and storms toward south central SD
in the afternoon and evening, in closer vicinity to a warm front
that is expected to lift northward across NE during the day.
Forecast CAPE and shear in that area Saturday afternoon do support
potential for strong to severe storms. A more widespread chance
for showers and storms should develop Sunday afternoon and
evening as the ridge shifts east and an upper level disturbance
likely crosses the northern Plains. The warm front is also
expected to be located across the forecast area, with an
approaching cool front to the west. At this time, there also looks
to be potential for strong to severe storms later on Sunday.
Above average temperatures will continue through a good portion,
if not all of next week, as a stronger ridge gradually builds over
the Rockies and into the high Plains. Highs in the 70s and 80s
will persist, with some 90s not out of the question by the end of
next week if the ridge builds far enough east into the Plains.
Potential for isolated/widely scattered storms persists early in
the week, but building ridge would lead to mainly dry conditions
for mid to late week.

&&

.AVIATION...(For the 18Z TAFS Through 18Z Friday)
Issued At 1031 AM MDT Thu May 30 2024

VFR conditions will continue through this evening. After midnight
or so, showers and isolated thunderstorms will develop across
portions of northeastern WY and western SD, resulting in some MVFR
conditions through Friday morning.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...None.
WY...None.
&&

$$

DISCUSSION/KEY MESSAGES...26
AVIATION...Pojorlie