635
FXUS63 KBIS 251715
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1215 PM CDT Wed Jun 25 2025

.KEY MESSAGES...

- Scattered showers and thunderstorms today, with isolated
  strong to severe thunderstorms possible later this afternoon
  into this evening mainly over southwestern North Dakota.

- Isolated severe thunderstorms possible again across the far
  west on Thursday.

- Chances are increasing for scattered severe thunderstorms on
  Friday with all hazards possible.

&&

.UPDATE...
Issued at 1143 AM CDT Wed Jun 25 2025

Currently, showers continue to track through the south central
and into the JRV late this morning. We had a period of gusty
easterly winds within the stratiform of the exiting precip over
the Bismarck Mandan area with 53 mph in Mandan and 44 mph at
the Bismarck Airport. Winds may also be gusty behind the
precipitation as it exits the JRV early this afternoon. To the
north, an area of showers have expanded from northwest int north
central ND and continue to lift off to the northeast. We
adjusted pops again, and tried to clear things out for at least
a short time over the southwest and south central behind the
exiting precip. We still have the potential for additional
thunderstorm development here later this afternoon and into this
evening.

UPDATE
Issued at 949 AM CDT Wed Jun 25 2025

Showers, moderate to heavy at times, with a possible rumble of
thunder continue to push east northeast through south central
ND. Another small area of showers and isolated thunder remains
around Williston and west into northeast Montana. This area is
lifting slowly northeast. Showers have exited the southwest at
this time. Additional strong to severe storms are possible over
the southwest later this afternoon into this evening. We
updated pops based on latest radar analysis and short term
guidance.

UPDATE
Issued at 636 AM CDT Wed Jun 25 2025

Isolated to scattered showers and thunderstorms continue over
parts of the forecast area, with the most organized
thunderstorms in the southwest/south central near the ND/SD
border. An occasional strong storm continues to develop, though
severe weather remains unlikely this morning. Adjusted Pops a
bit, otherwise the forecast remains on track.

&&

.DISCUSSION...
Issued at 446 AM CDT Wed Jun 25 2025

An active late June pattern continues with southwesterly flow
aloft being dominant through the remainder of the workweek,
followed by more zonal to northwesterly flow aloft this
weekend. There are low threats for severe weather today, mainly
in the southwest, and Thursday, mainly in the far west. However,
the highest chances for severe weather this week are on Friday
when the Gulf opens and mixed layer dewpoints from 65 to near 70
degrees stream into the state, especially the eastern two
thirds.

Currently, scattered showers and thunderstorms are present in
southwestern ND. With around 45 kts of 0 to 6 km bulk shear,
these storms have briefly become strong with small hail up to
the size of pennies and observed wind gusts from around 40 to 50
mph. However, a general lack of instability has prevented them
from becoming severe. Instability doesn`t begin to increase
until later this morning, and as is usually the case, more so
later this afternoon. Overall, the most favorable environment
appears to be in eastern Montana, and to a lesser extent in
western North Dakota late this afternoon, especially the
southwest where higher shear is expected to persist. As the sun
begins to set, instability decreases rapidly, while shear is
progged to decrease as well. Should any severe storms develop,
the primary threats for today include ping pong ball sized hail
and wind gusts up to 60 mph.

For Thursday, instability is expected to be higher in western
ND than today. However, shear is also likely to be weaker. With
skinny CAPE soundings and a lack of strong shear, pulsing
severe storms seem the likeliest outcome should any severe
weather develop. The current SPC outlook only pings the far
northwest in a marginal, likely due to capping issues over much
of the North Dakota side of the border and a lack of a good
forcing mechanism. Still, could foresee a few isolated strong to
severe storms in any of the western two tiers or so of counties
in ND. As a result, believe the primary threats are quarter
sized hail and 60 mph wind gusts.

Friday remains the day this week where severe weather is most
likely. Surface low pressure over the Rockies combined with
high pressure over the southeastern US will open the Gulf of
America and allow mixed layer dewpoints up to 70 degrees to
stream into the state, especially the eastern two thirds. This
will result in a buoyant atmosphere with soundings showing fat
CAPE profiles across central parts of the state. There may be
some capping issues in eastern North Dakota. However, shortwave
energy within southwesterly flow aloft, and a passing warm
frontal boundary with trailing cold frontal boundary, should be
able to overcome capping for central parts of the state, and
possibly the east as well. Shear may not be as strong as last
Friday with around 40 to 45 kts progged to coincide with the
highest instability. However, that is more than adequate to
produce very large hail and strong wind gusts. A tornado or two
is possible as well.

The severe threat continues into Saturday mainly for eastern
North Dakota and possibly the south central east of the
Missouri River. However, will want to see more clarity with the
Friday system and the timing of the frontal boundary first. If
the frontal boundary has already passed through the forecast
area, then with a more zonal flow system aloft following
Friday`s event, a good forcing mechanism may be hard to find.
Conditions are then favored to become mostly dry to start next
week.

Beyond severe weather chances, the two other things worth
mentioning are temperatures and smoke aloft. In regard to
smoke, elevated smoke is possible across the state today.
However, with mostly cloudy skies present and forecast to remain
across most of the state, that will be unnoticeable most of the
day for most locations. Temperatures today will be below
average. A warming trend is then on tap to finish out the
workweek with temperatures reaching a crescendo on Friday before
a slight cooling trend is favored for the weekend and into early
next week.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1143 AM CDT Wed Jun 25 2025

Currently, shower activity is exiting KXWA, KMOT and KJMS. We
may be able to start the 18Z TAF period out with no shower or
thunderstorm activity, or if not it should be short lived.

Later today, shower and thunderstorm activity is forecast to
develop around the ND/MT border and move eastward towards
central ND before dissipating later this evening. Confidence in
any one location is pretty low so will most likely go with a
Prob30 for western TAF sites for now and adjust as things
develop this afternoon.

Later tonight, widespread MVFR-IFR and possibly LIFR ceilings
are expected to develop over south central into southeast North
Dakota, and spread west and north to cover much of western and
central ND by Thursday morning. At this time the confidence is
higher for low ceilings than fog, although we do expect there
will be some fog, especially along the western fringes of where
the stratus sets up. As for the stratus the NBM 1D viewer
suggests over an 80 percent probability of MVFR ceilings tonight
with around a 55 percent probability of IFR ceilings and around
a 25 to 30 percent probability of LIFR ceilings at Bismarck
within the 1AM to 7AM timeframe. Probabilities are similar or
higher at KJMS but less for KDIK KXWA and KMOT. Low stratus and
fog should begin to dissipate later in the morning on Thursday.
Expect surface flow to remain east to southeast through the
period at 5-15 mph.

&&

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

&&

$$

UPDATE...TWH
DISCUSSION...Telken
AVIATION...TWH