641
FXUS63 KBIS 131852
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
152 PM CDT Sun Sep 13 2026

.KEY MESSAGES...

- High chances for rain showers (70-100%) late tonight into
  Monday. Greatest chances over central and eastern North
  Dakota.

- Becoming windy tonight, with the strongest winds expected on
  Monday before diminishing Monday night. Gusts around 50 to 60
  mph possible over western North Dakota. Wind Advisory in
  effect for most of the area on Monday.

- Occasional rain shower chances mid to late week.

&&

.DISCUSSION...
Issued at 108 PM CDT Sun Sep 13 2026

Latest water vapor imagery shows a ridge on the east side of the
Rockies and moving east into the Northern Great Plains. This
will keep much of the area under quiet and pleasant conditions.
A change in weather will occur later tonight. A low pressure
center, currently located over southeastern Washington, will
bring high chances for rain showers and increase winds.

Rain: The latest 12Z model convective allowing models have rain
starting as early as 1 AM MDT / 2 AM CDT, from the southwest
and expanding northeast through the rest of the morning. 12Z
HREF has over 75% chances for greater than half inch for the
event from Highway 52 and northeast. Chances for a quarter of
an inch or greater is 50% or higher from the Bismarck to
Williston and northeast. The southwest corner of the state has
lowest chances to receive anything above a tenth of inch, but a
few model members hint at a rumble or two which can add a little
more rain accumulation. Rain chances will diminish by the
midday to early afternoon, clearing from west to east.

Winds: At first, winds will predominately be from the
southeast today (in the southwest) and widespread tonight with
gusts up to 30 to 35 mph; the strongest winds will be in the
southwest portion of the state. As the low pressure center gets
closer, the pressure gradient will increase across much of the
state and switching the wind direction from the southeast to
more westerly to northwesterly. Winds will gust high as 50 to 60
mph by the afternoon. As result, there is a Wind Advisory in
effect starting at 12 PM CDT /11 AM MDT for the western half of
the area. The central and east will start 3 PM CDT. Winds will
start to relax by late Monday night.

Beyond Monday: Models show several weather disturbances passing
over the area, bringing chances for rain showers. The synoptic
pattern will bring a slight warming due to minor ridging.


&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1234 PM CDT Sun Sep 13 2026

VFR conditions expected for the remainder of the day. Conditions
will deteriorate from southwest to northeast by the late evening
with rain showers. Expect MVFR to IFR ceilings and possibly
lower visibility down to 2-3 miles after 06Z tonight.
Conditions will start to improve after 15Z to1 17Z from the west
to the east. Low chances for a rumble of thunder in the late
night to the morning.

Gusty southeast winds will develop later today primarily over
southwest North Dakota, with gusts to around 35 kts over far
southwest North Dakota by late afternoon. Gusty southeast winds
then spread northeast overnight across much of western and
central North Dakota. Gusty winds will shift to west to
northwest towards the end of the forecast period and gusting
high as 40 to 45kts.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from noon CDT /11 AM MDT/ Monday to midnight CDT
/11 PM MDT/ Monday night for NDZ001>003-009-010-017>020-
031>033-040>044-055>062.
Wind Advisory from 3 PM Monday to 4 AM CDT Tuesday for NDZ004-
005-012-013-022-023-025-035>037-046>048.

&&

$$

DISCUSSION...KJS
AVIATION...KJS