546
FXUS63 KBIS 121129
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
629 AM CDT Tue May 12 2026

.KEY MESSAGES...

- Critical fire weather conditions expected again today across
  central North Dakota, including the James River Valley.

- Strong winds expected across central and eastern North Dakota
  this morning through the afternoon.

- Windy conditions and low humidity values through the rest of
  the upcoming week may lead to daily critical fire weather
  conditions.

&&

.UPDATE...
Issued at 629 AM CDT Tue May 12 2026

The forecast remains on track.

&&

.DISCUSSION...
Issued at 456 AM CDT Tue May 12 2026

Windy and mostly dry conditions remain the story through the
remainder of the week. For today, surface low pressure currently
centered over Minnesota will gradually slide eastward into the
Great Lakes Region. Simultaneously, surface high pressure
currently over Montana will gradually nudge into the Dakotas.
This will result in a tighter pressure gradient over the eastern
half of the state today that should gradually loosen from west
to east. However, a trailing strong LLJ remains over much of
the state. These winds should mix down to the surface fairly
easily this morning resulting in very windy conditions this
morning and afternoon, especially for locations east of Hwy 83.
Depending on how quickly the gradient loosens and strong lower
level winds move off to the east will impact just how windy and
for how persistent winds will be today. Either way, winds will
rapidly diminish and become light and variable this evening. All
in all, the ongoing Wind Advisory looks good at this time.

Current NBM lows for tonight mostly range from 40 to 45 degrees.
However, with a good radiational cooling set-up, wouldn`t be
surprised if temperatures don`t wind up cooler than forecast,
especially in our traditionally colder spots. Depending on how
cold things get, frost development isn`t entirely out of the
question.

Come Wednesday, high pressure over the state will shift eastward
as the next surface low passes from west to east across southern
Canada. This will tighten the pressure gradient in western ND on
Wednesday, which is favored to produce windy conditions mainly
west of Highway 83 during the day that will then expand
eastward through the overnight hours. Very windy conditions are
then favored Thursday, especially in the northwest as an
enhanced EFI signal is starting to appear. An axis of increased
dewpoints looks to accompany the associated surface trough as it
moves through Wednesday night/Thursday. This, along with a mid-
level shortwave could produce isolated to scattered showers and
a few thunderstorms, although widespread wetting rains look
unlikely.

Even windier conditions are then possible Friday, especially
north of I94 where a further enhanced EFI signal shows higher
confidence in a stronger wind event. That said, current run
shows a shift of tails between 0 and 1 for most of the enhanced
signal. This doesn`t particularly favor an anomalous event, but
doesn`t rule one out either. Beyond Friday, winds remain breezy
to windy, though more widespread precipitation chances return.
Especially Saturday night where 45 to 55 percent precipitation
chances are present across the entire state.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 629 AM CDT Tue May 12 2026

VFR ceilings and visibility are generally expected through the
period. However, another windy day is on tap today, especially
east of Highway 83. This may result in patchy blowing dust that
could at least temporarily reduce visibility and possibly result
in the ASOS/AWOS network producing brief false ceilings. Should
patchy blowing dust develop, the terminal most likely impacted
would be KJMS, though confidence in this occurring at the
terminal is low. Winds will rapidly diminish this evening,
becoming light and variable.

&&

.FIRE WEATHER...
Issued at 456 AM CDT Tue May 12 2026

Winds are expected to ramp up again this morning, especially for
the eastern half of the state. As surface low pressure and
trailing low-level jet moves off to the east, winds should
gradually diminish from west to east this afternoon. However,
minimum relative humidity values are still expected to range
from 15 to 25 percent. It seems like winds should diminish
quick enough in western North Dakota to prevent critical fire
weather conditions from developing, but still advertising near
critical fire weather conditions should winds persist a little
longer. Based on these factors, the current Red Flag Warning
looks good as-is.

Encroaching high pressure will result in winds quickly becoming
light and variable across the entire state this evening as any
residual mixing is lost. For Wednesday, the next surface low
pressure will begin passing from west to east across southern
Canada. This will tighten the pressure gradient resulting in
another windy day in western North Dakota on Wednesday while
very dry conditions persist. As the low continues propagating
eastward, these windy conditions will further expand eastward
Wednesday night through Thursday, and then likely persisting
through Friday. Critical fire weather conditions are possible
each day. Isolated to scattered showers, and possibly a few
thunderstorms, may pass through mainly Thursday through Thursday
evening. However, widespread wetting rains seems unlikely.

Towards this weekend, cooler temperatures resulting in at least
somewhat higher RH values, as well as more widespread
precipitation chances, begin to enter the picture. The highest
probability for wetting rains are currently Saturday night
through Sunday. During this timeframe, most of western through
central North Dakota has a 20 to 40 percent chance of seeing a
wetting rain.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 11 AM this morning to 9 PM CDT this
evening for NDZ003>005-011>013-021>023-025-035>037-046>048-050-
051.
Wind Advisory until 7 PM CDT this evening for NDZ005-012-013-
022-023-025-035>037-046>048-050-051.

&&

$$

UPDATE...Telken
DISCUSSION...Telken
AVIATION...Telken
FIRE WEATHER...Telken