943
FXUS63 KFGF 022326
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
626 PM CDT Sat Aug 2 2025

.KEY MESSAGES...

- Air quality impacts will continue through Sunday due to
  lingering wildfire smoke.

- Scattered showers and isolated thunderstorms develop this
  evening and overnight across southeast North Dakota and
  northwest Minnesota, with locally heavy rain and lightning the
  main threats.

- Strong to severe thunderstorm chances return to the region
  next week, especially from Tuesday into the next weekend.

&&

.UPDATE...
Issued at 626 PM CDT Sat Aug 2 2025

Smoke continues to affect the region this evening and through
the overnight period. Storm system to the south has sparked a
few thunderstorms in northern SD this evening. These should
remain just south of the border this evening, with increasing
chances for showers and storms as we get into the overnight
hours. Otherwise, temperatures are in the 70s this evening with
overnight lows expected to drop into the upper 50s to lower
60s.

&&

.DISCUSSION...
Issued at 352 PM CDT Sat Aug 2 2025

...Synopsis...

Zonal H5 flow begins to shift slowly in the coming days,
becoming more southwesterly by the middle of next week. A cut
off H7 low will bring rain chances into mainly southeastern
North Dakota overnight tonight and into Minnesota through the
day on Sunday. Periods of moderate to heavy rain are possible,
as well as isolated thunderstorms. Heading into Monday and
Tuesday, a weak shortwave approaches the region, bringing
showers and thunderstorms back into the forecast for Tuesday.
Strong to severe storms will be possible from Tuesday through
the weekend as instability continues to build into the Northern
Plains and Upper Midwest. A stronger system could bring
additional chances for thunderstorm activity late next week and
into the weekend.

...Smoke Continues to Impact Air Quality...

Near surface smoke concentrations are slightly lower this afternoon
in eastern North Dakota, with northwest Minnesota still seeing the
higher concentrations. Visibility has been falling as low as 4 miles
at various times today, but recently have been above 5 miles at most
locations. Conditions are expected to continue a slow improvement
trend through Sunday.

...Showers and isolated thunderstorms tonight...

A slow moving H7 low continues to move eastward across the Northern
Plains this afternoon and evening, and will approach southeastern
North Dakota tonight into Sunday morning. Instability is rather weak
this evening, but will be increasing gradually Sunday morning. The
primary concern with this system is the slow progression combined
with the potential for moderately heavy rainfall rates. Any
thunderstorms at form tonight would likely be of the embedded type;
however, lightning would still be a risk. For Sunday, instability
increases slightly and could bring isolated storms capable of
producing small hail and heavy rain.

...Strong to Severe Thunderstorms Possible Next Week...

Ensemble guidance continues to indicate the potential for severe
thunderstorms next week, especially from Tuesday onward.
Westerly flow at 500mb turns more southwesterly Tuesday into
Wednesday, with a strong trough/upper low moving through the
area Thursday through Saturday. Ensemble suites disagree about
the timing, however, with the GFS/GEFS keeping an open wave, and
the ECMWF ensemble closing the wave into a much slower moving
upper low. Both ensembles show good instability, with shear
being dependent upon the timing of any associated shortwaves
preceding the upper low. Although exact spatial and temporal
details are minimal at this time, confidence is increasing that
there will be a favorable environment for severe thunderstorms
across parts of the area starting Tuesday, with particular focus
on the late week system.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 626 PM CDT Sat Aug 2 2025

Smoke continues to affect the region through the TAF period,
with occasional reductions to visibility this evening down to
5-7SM. Otherwise, we have breezy southerly winds gusting toward
25kts. This continues through sunset before going light out of
the southeast overnight. Rain and chances for storms increase
late tomorrow morning through the end of the TAF period as a storm
system moves closer toward the area. Potential for a few
showers in FAR around 12-14z. Ceilings go MVFR underneath
precipitation around 17-19z for all sites through the end of the
TAF period.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.

&&

$$

UPDATE...Spender
DISCUSSION...Lynch
AVIATION...Spender