-- Discussion containing changed information from previous version are highlighted. --
574
FXUS63 KFGF 130430
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1130 PM CDT Sat Jul 12 2025

.KEY MESSAGES...

- Wildfire smoke will degrade air quality today, with an
  additional round Sunday.

- There is a level 1 out of 5 risk for severe thunderstorms
  Monday. The main hazards are hail, gusty winds, and flash
  flooding.

&&

.UPDATE...
Issued at 959 PM CDT Sat Jul 12 2025

Smoke continues to push eastward this evening. Once again, there
will be a break overnight but there will be another batch
tomorrow. Quiet weather continues regardless so no major updates
to the current forecast.

UPDATE
Issued at 634 PM CDT Sat Jul 12 2025

Smoke continues to linger across the region. There is a band of
clearing that will occur sometime this evening and overnight but
expect additional smoke to come in and last through the day
tomorrow.

&&

.DISCUSSION...
Issued at 258 PM CDT Sat Jul 12 2025

...Synopsis...

Upper trough on water vapor is pulling eastward into the Great
Lakes, with northwesterly flow aloft setting up for tonight and
into tomorrow. This will bring not much for precipitation
chances but will help shift wildfire smoke from Canada down into
our area. Flow becomes more zonal for Monday, which will help
decrease smoke impacts but increase thunderstorm chances.
Precipitation chances will continue into Tuesday as a cold front
pushes down into the Northern Plains. Falling heights with a
broader trough digging down into the region will bring some
cooler than average temps for the end of the week. Low
predictability for precipitation chances as various weak
shortwaves move through.

...Smoke tonight and tomorrow...

Sat loop shows some thinning of the smoke layer over western
portion of ND, and there has been some locations west of the
Missouri River seeing visibility improvement. Both the HRRR and
Canadian models show some improvements to surface smoke
concentration for later tonight into Sunday morning. However,
there will be another weak cold front coming down tomorrow and
there could be some more smoke coming down to the surface with
subsidence. Exact timing of the break in the smoke and then the
return is uncertain, but should continue to see unhealthy to
very unhealthy air quality through the rest of the weekend.

...Marginal severe chances Monday...

Some moisture return for the beginning of the work week will
help probabilities for CAPE values over 2000 J/kg increase to
over 50 percent Monday afternoon. Deep layer bulk shear is
fairly robust as flow becomes more zonal, up to 40 kts. However,
much will depend on where exactly the surface boundary ends up,
which models have all over the place. At this point think the
severe impacts look pretty isolated, but will continue to
monitor.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
-- Changed Discussion --
Issued at 1128 PM CDT Sat Jul 12 2025

The main aviation impact will continue to be smoke. MVFR to IFR
visibilities can be expected at times for the entire TAF period.
Brief breaks to VFR can be expected as ceilings will remain VFR,
but for the most part MVFR should be the primary visibility.
A front will push through tomorrow morning shifting winds to
more northwesterly, ending the break in smoke and bringing
another swath down. Wind gusts behind this front should max out
around 25 to 30 knots with sustained winds between 10-20 knots
depending on sheltering near TAF sites (more forested areas like
BJI should have winds lower). Wind speeds will remain elevated
above 6 knots in the evening but will diminish to mainly the
single digits to low double digits after 00z.
-- End Changed Discussion --

&&

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

&&

$$

UPDATE...Perroux
DISCUSSION...JR
AVIATION...Perroux