723
FXUS63 KBIS 290539
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1239 AM CDT Fri Aug 29 2025

.KEY MESSAGES...

- Near seasonable high temperatures in the mid 70s to mid 80s
  today through Labor Day, with lows generally in the 50s.

- Low chances for showers and thunderstorms, mainly south,
  Friday through Labor Day. The probability for severe weather
  is very low.

&&

.UPDATE...
Issued at 1238 AM CDT Fri Aug 29 2025

Little updates needed at this time. Abundant mid to high clouds
have moved into the area. Some chances for showers will be found
in the far southwest tonight, with perhaps an isolated
thunderstorm also possible. Overall the forecast remains on
track.

UPDATE
Issued at 942 PM CDT Thu Aug 28 2025

Clouds continue to increase across the forecast area. Radar
shows shower activity getting close to the far southwest, but
moving very slow. Utilized a blend of current forecast and
latest short term guidance. Overall, very little changes needed
to the going forecast.

UPDATE
Issued at 553 PM CDT Thu Aug 28 2025

Made some minor adjustments to sky cover, otherwise no changes
planned at this time.&&

.DISCUSSION...
Issued at 245 PM CDT Thu Aug 28 2025

This afternoon, the synoptic pattern was characterized by a
strong northern stream wave extending through the eastern
Canadian Prairies, with a southern stream quasizonal flow across
the Southern Plains. In between these is relatively diffuse
flow across the Dakotas, with a stretched low and tilted trough
attempting to develop across the Pacific Northwest. At the
surface, a weak frontal boundary was analyzed across the
northeast corner of the state. Near to slightly above average
temperatures continued today, with forecast highs in the 80s.
Some fair weather cu has been bubbling over the past hour or so,
with cirrus from the upstream wave in Montana slowly expanding
over the forecast area.

Main change with this update was to slightly increase POPs across
mainly north central North Dakota this afternoon to get mention of
slight chance rain showers. Some high-res model runs have been
relatively persistent in developing isolated showers and perhaps a
thunderstorm or two in this general vicinity as the
aforementioned boundary slowly drifts southwest through the
late afternoon and into the evening. Per deterministic
guidance, instability is very low, although SPC RAP-based
mesoanalysis has around 1000 J/kg of surface- based CAPE. Not
the highest confidence in anything developing but thought it was
worth a mention for a few hours later today. Did also think
about adding in mention of patchy fog in the James River Valley
tonight, but ultimately thought probability was too low at this
point for impactful visibility reductions.

Precipitation chances increase across the southwest and south
central tonight through Friday and Saturday as a shortwave and
attendant surface low track through South Dakota, keeping the bulk
of precipitation to our south. The likelihood of receiving even
0.10" of QPF across the far southwest and south central is only
around 25 to 45 percent, which is the general maximum chance of
precipitation overall from tonight through Saturday in these
areas. The synoptic flow gets a bit messy for the back half of
the holiday weekend, with very broadly northwest flow aloft
eventually developing. Blended POPs are low and on and off
Sunday and Monday, before increasing and becoming more
widespread on Tuesday with more ensemble agreement on a
shortwave sliding through the cyclonic flow. Throughout this
entire period, NSSL and CSU machine learning probabilities
continue to advertise no real chance for severe thunderstorms.

Temperatures will be quite consistent for the holiday weekend, with
highs generally in the mid 70s to mid 80s Friday through Monday, and
lows mainly in the 50s. With the aforementioned shortwave on
Tuesday, there is good consensus in a short-lived cooling trend
for the middle of next week, with current NBM deterministic
highs in the 60s on Wednesday before we start to warm up again
for the end of the week.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1238 AM CDT Fri Aug 29 2025

Mainly VFR conditions are expected through the forecast period.
Mid to high level clouds will be found to most sites through the
period. Low VFR to perhaps MVFR ceilings may be found from KDIK
to KBIS to KJMS and southward Friday through Friday evening.
Confidence was not high enough to include MVFR ceilings at this
time. A chance for showers and isolated thunderstorms may be
found in the southwest tonight, spreading to much of southwest
and south central North Dakota Friday. Confidence was not high
enough to include any precipitation mention on the TAFs at this
time. Winds will be light and variable tonight, becoming a light
east southeast wind on Friday.

&&

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

&&

$$

UPDATE...Anglin
DISCUSSION...Jones
AVIATION...Anglin