869
FXUS63 KBIS 031144
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
644 AM CDT Wed Sep 3 2025

.KEY MESSAGES...

- Areas of smoke linger over many parts of the area today.

- Strong cold front passes through Thursday, with wind gusts
  around 45 mph in its wake.

- Areas of frost possible early Saturday morning.

&&

.UPDATE...
Issued at 638 AM CDT Wed Sep 3 2025

For lack of a better way to put it, visibility is kind of a mess
over parts of western North Dakota. Wildfire smoke is already reducing
visibility over the area, and with the calm winds some fog has
also developed reducing visibility even more. Given the hit and
miss nature of the fog, and trouble discerning it from smoke in
some spots, have broad brushed areas/patchy fog through much of
western and central North Dakota for a few hours this morning.


&&

.DISCUSSION...
Issued at 430 AM CDT Wed Sep 3 2025

Current surface analysis places low over Lake Superior into
southern Ontario, while cold front stretches through the upper
midwest into the central plains. Behind the cold front, high
pressure continues to settle through the Canadian prairie
provinces nudging into the northern plains. Upper level analysis
places low over western Ontario and high stretching from
southern British Colombia south-southeastward towards the Four
Corners area. Over our area, upper level north-northwest flow
continues. Isolated showers have pushed to the south, but areas
of wildfire smoke continue.

For today, a quiet day is on tap while wildfire smoke continues
to settle southward. Temperatures will be quite cool in the wake
of the aforementioned cold front with high temperatures running
about 15 to 20 degrees below average.

Warmer air tries to nudge back into the area tonight, but this
will be very short lived as a fast moving upper level short
wave and its affiliated cold front push through the area
Thursday morning. Latest NBM guidance is showing about a 50-80%
chance of seeing wind gusts of 45 mph or higher over a broad
swath of western and central North Dakota, while only about a
20% chance over some areas of seeing gusts of 55 mph or higher.
With that said, previous runs along with the current run of the
ECMWF Extreme Forecast Index continues to show a broad swath of
values 0.9 or greater through western/central North Dakota
which is indicative of higher wind values. Even a look at
forecast soundings is showing the possibility of 50kt winds
mixing down. Therefore, will advertise expected gusts of 50 mph,
but will keep a close eye on how this evolves today to see if
we need to bump it up a bit or hold steady.

A breezy but chilly day is expected on Friday as cold air
continues to settle in, with highs only expected to climb into
the mid 50s to lower 60s. High settles in overnight with winds
tapering, which will probably bring areas of frost to many
locations, especially to the typical frost-prone areas of
southwest into west-central North Dakota.

A gradual warming trend is on tap to start out next week along
with dry conditions as upper ridge over the western CONUS
gradually works its way towards the plains.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 638 AM CDT Wed Sep 3 2025

Wildfire smoke continues to reduce visibility to MVFR levels,
dipping to IFR in some locations. In addition, some fog has also
developed over parts of western and central North Dakota further
reducing visibility in spots. Expect some improvement as the day
goes on, with smoke starting to clear out from north to south
later today, but some smoke may linger well into the evening,
especially over southwestern North Dakota. Early Thursday
morning, a cold front will start to push its way into far
northwest North Dakota. Behind the front, wind gusts of 40kts
will be possible.

&&

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

&&

$$

UPDATE...JJS
DISCUSSION...JJS
AVIATION...JJS