776
FXUS63 KBIS 022343
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
643 PM CDT Wed Sep 2 2026

.KEY MESSAGES...

- Low to medium chances of showers and thunderstorms in western
  North Dakota late this afternoon and evening, and in central
  North Dakota tonight into Thursday. Isolated severe
  thunderstorms are possible, mainly in western North Dakota
  this evening.

- Low chances of thunderstorms Friday and Saturday, then medium
  to high chances for showers and thunderstorms Sunday through
  early next week.

- Expect a warming trend through the end of the week, then
  cooling somewhat late this weekend into early next week.

&&

.UPDATE...
Issued at 629 PM CDT Wed Sep 2 2026

In general, the forecast remains on track for tonight. We`re
monitoring the progress of a few isolated showers and storms
across eastern Montana and northwestern South Dakota. While
convective inhibition is expected to increase over the next few
hours with the loss of diurnal heating, it`s possible some of
this activity could make it to western North Dakota before
decreasing in intensity late tonight. While chances remain low
(20-30%), there is an outside chance of a rouge severe storm
sneaking into western North Dakota before midnight.

&&

.DISCUSSION...
Issued at 249 PM CDT Wed Sep 2 2026

Southwesterly flow aloft continues across the Northern Plains as
a warm front moves through eastern Montana into North Dakota
later this evening. Storms could fire along the front this
evening as ample instability remains in place across eastern
Montana into western North Dakota. However, forecast soundings
show that there will be a very strong CAP the further east you
go into North Dakota later this evening mainly impacting
anything that wants to move in the south central. Some of the
CAMs try to bring a stronger storm across the southwest this
evening and a cluster of weaker storms across the northwest
along the front. The southwest storms are less in coverage now
as the models have pulled back slightly. CAMs are increasing
their coverage of storms developing in the early morning hours
across the north central. SBCAPE tomorrow morning and afternoon
will range around 1500-2500 j/kg of cape and 40 kts of shear.
Storms will likely progress and strengthen by the early
afternoon across the north central moving across eastern North
Dakota into western Minnesota.

High temperatures this afternoon are forecast to warm into the
80s across the state. Overnight low temperatures tonight are
forecast to drop down into the upper 50s to lower 60s. A weak
low level jet will continue tonight moving eastward with the
frontal progression. This could lead to breezy conditions and
sustained storm development tonight across eastern and central
North Dakota. Tomorrow, temperatures are forecast to warm into
the warm upper 70s north to the upper 80s south. The warmer
weather will move into the region by the end of the week as an
upper level ridge builds across the region. Temperatures, Friday
are forecast to warm into the upper 80s to lower 90s.

The upper level ridge is forecast to break down by this weekend
leading to cooler temperatures. The ridge breaking down will
open the door for an upper level low to move through the region
Sunday into Memorial Day bringing forth increased chances of
rain. The probabilities continue to increase for 1 inch of rain
where the north now has around 50 percent shot of an inch of
rain. The NBM 25th to 75th percentile for KBIS are around the
70s for later next week as the ridge breaks down.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 629 PM CDT Wed Sep 2 2026

Scattered showers and storms are forecast portions of
northwestern and north-central North Dakota late tonight into
Thursday morning. Mainly forecast to impact KXWA and KMOT, the
primary concerns with this activity would be a few lightning
strikes, gusty winds, small hail, and brief reductions in
visibility from heavy rainfall. In general, timing for storms
will be between 08Z-18Z Thursday.

Elsewhere, VFR conditions are forecast to prevail. Though, it
should be noted that a low chance (under 20%) of an isolated
storm is possible at KDIK, KBIS, KJMS, and surrounding
locations, and amendments may be necessary if that occurs before
06Z.

Surface winds will be fairly consistent out of the east and
southeast at around 10 to 15 knots with gusts around 20 to 25
knots over the first 12 hours of the TAF period. Then, surface
winds will gradually become light and variable as a weak
surface ridge slides across the region Thursday morning and
early afternoon.

&&

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

&&

$$

UPDATE...JC
DISCUSSION...Johnson
AVIATION...JC