819
FXUS63 KFGF 312338
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
638 PM CDT Mon Aug 31 2026

.KEY MESSAGES...

- Gusty southwest winds to 50 mph in northeast ND this
  afternoon will bring minor wind impacts. Wind Advisory in
  effect through 7 PM.

- Chance for thunderstorms returns mid to late this week. This
  includes potential for strong to severe storms, however,
  confidence remains low regarding details.

- Late summer heat forecast to return this weekend.

&&

.DISCUSSION...
Issued at 231 PM CDT Mon Aug 31 2026

...Synopsis...

Water vapor imagery this afternoon reveals a well defined upper
low in SK/MB, with its southern flank and dry slot over ND. This
is contributing to gusty southwest winds, including 50 mph gusts
in northeast ND this afternoon. This upper low migrates eastward
Tuesday, keeping breezy winds in the forecast Tuesday afternoon.

Drier, post-frontal air mass behind last night`s cold front will
remain in place over our area Tuesday into Wednesday. Calm,
cool, and likely mostly clear conditions in addition to recent
rainfall will allow potential for fog Tuesday night/Wednesday
morning.

Into mid week around Wednesday, upper ridging begins to build
into the Northern Plains downstream of a longwave upper trough
digging into the Pacific Coast. This will promote moisture
return into the Northern Plains and Upper Midwest late Wednesday
and Thursday. This continues as upper ridging further builds
into the Plains in response to the digging and non-progressive
upper troughing in the West. This will several days of southwest
flow aloft over our region allowing for continued and somewhat
lengthy period of moisture and heat return through late week
into the weekend. This will bring ingredients into the Northern
Plains and Upper Midwest for potential strong to severe storms
as well as late summer heat with potential for minor heat
related impacts.

Ensemble guidance suggests the upper trough and ridge
wave packet breaks down into early next week, which typically
would signal the end of heat and severe potential. However,
there are notable difference between ensemble systems in how
this breakdown evolves - thus confidence in the extended
forecast is low.

...Gusty winds this afternoon...

A tightened surface pressure gradient collocated with
relatively deep mixing in northeast ND is allowing for southwest
wind gusts 40-50 mph. This is expected to continue through the
afternoon until around sunset when deep daytime mixing begins to
cease. Wind gusts will rapidly dwindle, although breezy winds
10-15 mph are expected to continue through the overnight. While
40-50 mph gusts are not typically impactful for northeast ND,
seasonal factors like full foliage on trees, as well as this
area not experiencing these longer duration high of gusts in
over a month or two will contribute to bring low impacts from
gusty winds. A Wind Advisory will remain in effect until 7 PM
for this area.


...Potential strong to severe storms mid to late this week...

Starting late Wednesday into Thursday, several model guidance
systems bring one or more shortwave impulses within the initial
surge of southwest flow aloft as the upper ridge brings to
build. This also houses increasing overall moisture that
remains pooled in the southern half of the CONUS along with
steepening lapse rates aloft sourced from the Central Rockies.
Guidance brings low but sufficient parameter spacing with
respect to instability and shear late Wednesday to early
Thursday timeframe. This lends some credence in strong to severe
storms being more on the lower end of severity, as well as
likelihood of storms being elevated bringing hail to the
forefront of potential hazards.

Overall, there are no glaring signals for significant severe
weather despite there being several opportunities for
ingredients for severe weather to come together mid to late this
week. This is backed by ML/AI guidance highlighting our region
late Wednesday through Saturday for severe potential.

It is worth noting this pattern could result in locally heavy
rain and potential for flash flooding given the longer duration
of moisture flow and an upper pattern that is non-progressive
potentially allowing for several shortwave impulses to traverse
through our region. Confidence in this is low, however, as there
are unknown mesoscale influences that are necessary for flash
flooding yet to be correctly resolved by modeled guidance.

...Late summer-like heat this weekend...

Ensemble guidance strongly suggests in strong upper ridging into
the Upper Midwest this weekend. This will promote increasing
temperatures aloft, as well as the migration and pooling of
moisture near the surface. This will not only allow opportunity
for 90s back into the forecast, but also high humidity. As of
now, Friday and Saturday look to be the days where these two
may align to bring heat indices well into the 90s, and perhaps
into the low 100s (10 percent chance of occurring). While
Saturday looks to be hottest within the forecast period, this
could also extend into Sunday, although confidence is low in
this.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 638 PM CDT Mon Aug 31 2026

VFR conditions prevail through the period with wind dropping
off this evening by 03z for all sites. West winds overnight
slowly build again through the morning back to 10-15kts with
gusts at or above 20kts from 15-22z before gusts drop off again
in the late afternoon.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...Wind Advisory until 7 PM CDT this evening for NDZ006>008-
     014>016-026-027-054.
MN...None.

&&

$$

DISCUSSION...CJ
AVIATION...TT