242
FXUS63 KBIS 170938
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
438 AM CDT Tue Jun 17 2025

.KEY MESSAGES...

- Patchy fog possible in central and eastern North Dakota this
  morning.

- Active pattern with periodic shower and thunderstorm chances
  during the workweek into the weekend. A few severe storms are
  possible, more notably later in the week.

- Overall temperatures remain around normal to slightly above
  normal for this time of year.

&&

.DISCUSSION...
Issued at 429 AM CDT Tue Jun 17 2025

Surface high pressure over eastern Montana will continue to push
into North Dakota today. This will lead to relatively quiet
weather across the state. High temperatures are forecast to warm
into the 70s to lower 80s this afternoon. Surface high pressure
will keep the skies fairly clear throughout the day. Winds will
eventually switch to northerly by the afternoon, but remain
light. No precipitation is forecast today. Overnight low
temperatures are forecast to drop down into the 50s tonight.

The upper level pattern remains zonal in the short term. An
upper level shortwave is forecast to move into the region
early tomorrow morning bringing in chances for showers and
thunderstorms throughout the day. The environment tomorrow does
support isolated strong to severe storms with around 1500 j/kg
of SBCAPE and 20-30kts of 0-6 km wind shear by the afternoon to
evening hours. Modest lapse rates and cooler temperatures aloft
could support multi-cluster cells across the northern half of
the state possibly producing large hail and strong to severe
wind gusts. The Storm Prediction Center has most of central and
eastern North Dakota in a marginal risk for severe weather
Wednesday.

High temperatures Wednesday are forecast to climb up into the
80s across the region. Overnight low temperatures are forecast
to drop down into the 50s again. Temperatures will warm up
Thursday into the upper 80s in the southwest to the upper 70s in
the northeast. High temperatures will gradually drop down into
the lower to mid 80s until Sunday, when an upper level low
moves through the region bringing in cooler temperatures.

An upper level ridge over the Pacific Northwest will begin to
push over the Northern Rockies into the Northern Plains by the
end of this week. Southerly return flow will begin to advect 60
dew points back into the region Thursday with temperatures in
the 80s will lead to increased instability across the state. The
ensembles have MUCAPE around 1000-2000 j/kg and 45-55 kts of
0-6 km wind shear, which would support supercell development.
The only thing holding back severe weather Thursday is the lack
of a forcing mechanism to break the cap. Therefore, the Storm
Prediction Center has most of central and eastern North Dakota
in a marginal risk for severe weather Thursday. CSU machine
learning program and NSSL machine learning severe probability
program are both picking up on Friday and Saturday having the
highest probability of severe weather. Friday, an upper level
short wave is forecast to move across the state. The environment
will be similar to Thursday, but with a lifting mechanism. The
machine learning programs are also pegging Saturday to have
another round of severe storms as another strong wave moves
across the jet stream.

An upper level low is forecast to move through the region Sunday
bringing forth precipitation and cooler temperatures next week.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1246 AM CDT Tue Jun 17 2025

VFR conditions will continue across the state today. There is a
low chance in patchy fog forming in low areas, the TAFs will be
amended if fog forms. Winds will remain light and variable this
morning veering to northwesterly to northerly this afternoon.

&&

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

&&

$$

DISCUSSION...Johnson
AVIATION...Johnson