241
FXUS63 KBIS 121128
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
628 AM CDT Sat Jul 12 2025

.KEY MESSAGES...

- Areas of smoke exit the forecast area from west to east today.
  Otherwise, dry with a warming trend through the weekend.

- Turning cooler north on Monday but remaining hot south. Highs
  ranging from the mid 70s far north to the mid 90s far south.

- Medium chances (30 to 60 percent) for showers and
  thunderstorms Monday through Monday night, some storms could
  be strong to severe central and south.

- Notably cooler mid-week with periodic chances for showers and
  thunderstorms.

&&

.UPDATE...
Issued at 619 AM CDT Sat Jul 12 2025

No updates needed. With the previous update, we added patchy
fog for a few hours early this morning based on satellite
imagery.

UPDATE
Issued at 515 AM CDT Sat Jul 12 2025

Quick update to add some patchy fog over much of the CWA.
Thinking this is shallow fog and the combo of fog/smoke is
probably making vsbys lower than if it were just fog. Fog should
burn off pretty quickly this morning.

&&

.DISCUSSION...
Issued at 355 AM CDT Sat Jul 12 2025

Currently, surface high pressure centered near the Black Hills,
covered western portions of the Northern Plains. A lee side
trough was situated over the Canadian and Northern Rockies with
a southerly return flow over the Northern High Plains.

The surface trough will push east this morning, into the central
and eastern Dakotas. A southwest surface flow and a west to
northwest mid to upper level flow will help push the smoke that
is currently over western and central ND, out of the forecast
area today. Otherwise, expect a dry and warm day with highs in
the upper 70s Turtle Mountains to the mid and possibly upper 80s
far west. Disregarding the smoke, we will see initially clear
skies this morning, but with some increasing high and mid level
clouds this afternoon associated a northern stream trough
tracking through Canada.

Tonight, the weak and dry surface cold front associated with
the Canadian trough tracks southeast through the forecast area
with nothing more than a wind shift with the frontal passage.
Not as cool tonight with lows mainly in the mid 50s to lower
60s.

On Sunday we see anther warm and dry day, with highs a few
degrees warmer than today. After mostly light southwest winds
today, we see breezier northwest winds on Sunday, strongest in
the north central into the James River Valley, where we could
see some afternoon gusts into the 25 to 35 mph range. Based on
the latest guidance, we could see another lobe of smoke clip our
northeast CWA on Sunday, with higher concentrations remaining
north and east of the CWA.

Monday begins the transition from broad upper level ridging
over the western half of the U.S. and a northwest upper flow, to
more of a zonal flow as a series of waves that track along the
International Border, under a developing Hudson Bay low. This
will bring a noticeably cooler airmass to the forecast area for
the Tuesday - Thursday timeframe. But before we get to that, we
might see some showers and thunderstorms Monday afternoon and
evening, some strong to severe. Yesterday we mentioned this
potential but the CSU ML page indicated the severe potential was
just south of the state. It has now sneaked up into southern
North Dakota. SPC has also introduced a marginal risk (level 1
of 5) of severe storms over southwest and into central North
Dakota. A quick look at the forecast temperatures Sunday can
give you an idea of the storm potential. Highs are forecast in
the mid 70s in the far north, to the mid 90s far south. We will
see an east to west frontal boundary dropping south with at
least moderate instability to the south of the boundary.
Moderate bulk shear south of the boundary will increase to
strong shear along and north of the boundary. We will certainly
need to continue to monitor the potential for severe storms
Monday afternoon into Monday night.

After the initial boundary pushes south through the area Monday
night, there is a lot of uncertainty in how the mid-upper level
flow shakes out. The threat for severe storms look to be low,
but periodic chances for showers and perhaps a thunderstorm will
be possible through mid-week. Currently our NBM pops depict low
to medium chances for precipitation in the Tuesday through
Thursday timeframe. Wednesday currently looks to be the coolest
day with highs mainly in the 60s across the forecast area. Then
perhaps a slow warm-up as we head into next Weekend.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 619 AM CDT Sat Jul 12 2025

MVFR to IFR visibilities at KXWA, KDIK and KMOT to begin the 12Z
TAF period in smoke and fog, with only smoke at KJMS. Fog
should dissipate by around 14-15 UTC. Short term models show
smoke exiting the area from west to east this morning. By this
afternoon expect only mid and high level cloudiness with
southwest to west winds generally 10 to 15 mph. Winds diminish
early this evening and shift to the south. Winds remain light
overnight but do shift west to northwest from west to east
behind a dry cold front.

&&

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

&&

$$

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