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000
FXUS63 KBIS 232055
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
355 PM CDT Tue Apr 23 2024

.KEY MESSAGES...

- Decreasing winds this afternoon as surface high pressure
  moves into the region.

- Above normal temperatures Wednesday and Thursday, with
  widespread highs in the 70s likely on Thursday. Breezy
  southwest and south central

- A pattern shift begins Thursday and continues through the
  weekend. Showers and thunderstorms are possible (50-70%)
  Thursday afternoon through Friday, with the highest
  probabilities across southern half of the state.

&&

.DISCUSSION...
Issued at 347 PM CDT Tue Apr 23 2024

A surface low continues to push into the Great Lakes region
while surface pressure moves in from eastern Montana. Daytime
heating has mixed stronger winds aloft down to the surface, thus
resulting in the breezy to windy conditions across central and
eastern North Dakota. Winds are finally beginning to decrease
across the western half of the state as surface high pressure
moves in from the west. Clear skies and subtle ridging across
the Northern Rockies has lead to warmer conditions across the
state. High temperatures are forecast to reach the upper 50s to
lower 60s this afternoon while low temperatures are forecast to
remain near or slightly above freezing.

Weak ridging will build over the Northern Plains Wednesday and
Thursday leading to warmer weather. Temperatures Wednesday are
forecast to warm into the lower 60s to lower 70s out west. A
weak short wave will move through the region late Wednesday
afternoon leading to increased cloud cover during the day. The
aforementioned short wave could produce virga as there will be a
very dry level near the surface. A surface low off to the west
and surface high pressure off the east will usher in a north
south pressure gradient resulting in breezy conditions across
the state. There is a possibility of near critical fire weather
conditions across the northwest tomorrow afternoon as breezy
southerly winds could overlap with 20 to 25 percent minimum
relative humidity.

Temperatures will continue to trend upward in the 70s Thursday
as the ridge passes overhead. Windy return flow will increase
humidity across the state as warm moist air is advected into the
region. This will result in increase instability especially
across the southwest. A shortwave trough is going to move across
the Northern Rockies into the Northern Plains Thursday
resulting in increased chances for precipitation by the evening
hours. Increased instability ranging from 500-1000 j/kg and
lapse rates around 7 C/km will allow thunderstorm development as
the trough pivots northward. CSU Machine Learning Program does
have a low probability for large hail. Shear looks rather lack
luster with 0-500 mb shear around 20 kts.

Broad troughing across western and central CONUS will dominate
the pattern this weekend. An upper level low is forecast to
pass over eastern North Dakota bringing in precipitation chances
Thursday evening through Sunday. The greatest chances for rain
is Friday into Saturday as the southeastern half of the state is
favored for precipitation while the northwest could miss out
entirely. Portions of south central and southeastern North
Dakota have around a 60-80 percent chance for 0.25 inches of
rain through the weekend. After the weekend the pattern could
remains fairly active later next week.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1256 PM CDT Tue Apr 23 2024

VFR conditions will continue through the latest TAF cycle. Winds
will begin to veer from the north this afternoon to the south by
tomorrow morning. Gusty afternoon winds around 20kts are still
possible at KJMS and KBIS, but winds will continue to trend
downward through the evening. Some scattered cumulus is forming
across the south but will remain around 5000 ft and will
diminish around sunset.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Johnson
AVIATION...Johnson