488
FXUS63 KFGF 081729
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1229 PM CDT Tue Jul 8 2025

.KEY MESSAGES...

- Severe storms are possible, risk level 1 out of 5, Wednesday
  evening and late Thursday afternoon and night.

&&

.UPDATE...
Issued at 1229 PM CDT Tue Jul 8 2025

Status deck continues to erode in west central MN. A bit more
in the way of towering cu in north central MN where there is
some elevated instability. However, these cells are headed into
an area with higher heights and limited instability, so don`t
think we will see much more than a couple of sprinkles at best.
Better convective chances hold off until late tomorrow evening.

UPDATE
Issued at 954 AM CDT Tue Jul 8 2025

Patchy fog has burned away at most locations, with only portions
of MN lake country still around 4 miles visibility. Stratus deck
over our southeastern counties has started the process of
scattering out and looks more cumuliform on satellite. Should
continue to decrease as we continue through the day. Otherwise
pretty quiet with temps in the upper 50s and 60s. Still seems on
track to hit the 70s as we clear out.

UPDATE
Issued at 659 AM CDT Tue Jul 8 2025

Low level clouds cover is moving south with clearing into the
northeast ND and far northwest MN at 11z. Patchy fog continues
with localized dense spots, but webcams show it is still rather
patchy and will maintain current messaging as the fog will burn
off thru mid morning.

&&

.DISCUSSION...
Issued at 314 AM CDT Tue Jul 8 2025

...Synopsis...

The 500 mb short wave that has been riding the border is moving
east with the last of the rain and t-storms moving out of the
Lake of the Woods. Thus for today into tonight and most of
Wednesday a dry period for eastern ND and northwest and west
central MN. Weak high pressure moving in. We have patchy fog and
low clouds currently at 08z and may well see more expansive area
of that heading thru 12z, before burning off/clearing off mid
morning.

Once any fog/low clouds go away, it will turn out to be a partly
cloudy day with likely some aftn CU due to surface heating and
remains of 850 mb moisture.

Clear Tues night into Wed AM with winds turning light southerly.


...Severe chances Wednesday...

Wednesday daytime hours look dry with an increasing south-
southeast wind. Near 90 Devils Lake to 80s farther east. We wil
start to see the spread north of low level moisture in terms of
dew pts near 70 late in the day into DVL region, vs upper 50s in
north central MN. 850 mb winds south-southwest 25 kts along with
warmer and more moisture moving in at 850 mb will bring the risk
of elevated convection Wed evening and night. There is also a
weak short wave, but that looks to be south in South Dakota.
Therefore uncertain on coverage of storm development Wed
eve/night.  Hence isolated marginal risk.

...Severe chances Thursday...

South winds will continue to bring up low level moisture as dew
pts reach the low 70s all areas by Thursday aftn. Local dew pts
mid or upper 70s due to evapotranspiration. Temps around 90 for
highs. The stage is set for Sfc CAPE values to reach 3500-4000
j/kg. Warmer temps at 700 mb and soundings show a warm layer but
not strong enough I think to hold back convective development.
GFS/ECMWF generally indicate weakening cap 21z-00z. If temps can
warm as forecast and dew pts are as fcst...GFS soundings show
4500 j/kg sfc CAPE and minimal CIN at 00z Fri in eastern ND. But
there are negatives such as a positive tilt on 500 mb trough to
our west and thus no real cooling in the 500 layer. Weak sfc
trough will be well out ahead of the 500 mb trough with a weak
boundary, wind shift, line likely somewhere from northeast to
south central ND at 00z. Some weak short waves may also be
present per GFS. All in all, stage is set that if storms form
they could be explosive with all hazards late Thu aftn/night.
SPC is cautious based on the above and has area in level 1 out
of 5 (Marginal) for Thursday in our area based on some of the
negatives against explosive severe storm development.


Going into Friday and Saturday.... 00z GFS/ECMWF and most
ensembles now support a faster exit of the 500 mb wave and not a
closed 500 mb low that has been showing up in some past runs. If
that is the case, then precipitation chances will move out
Friday night. Another in the endless stream of short waves moves
ESE to near Winnipeg (ECWMF) or central Manitoba/Saskatchewan
(GFS) with chance of storms late Sunday or Monday but small
chances at this time due to uncertainty how far south the wave
travels toward the border.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1229 PM CDT Tue Jul 8 2025

MVFR ceilings still hanging around KFAR and KBJI with stratocu
deck, but should scatter out in the next few hours. Light north
winds under 10 kts will become variable this evening with all
sites going VFR. Winds picking up out of the southeast late in
the period.

&&

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

&&

$$

UPDATE...Riddle/JR
DISCUSSION...Riddle
AVIATION...JR