664
FXUS63 KFGF 031217
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
717 AM CDT Wed Jun 3 2026

.KEY MESSAGES...

- There is a level 2 out of 5 risk for severe thunderstorms this
  afternoon and evening over the central and southern Red River
  Valley.

&&

.UPDATE...
Issued at 336 AM CDT Wed Jun 3 2026

Tweeked pop grids a bit to match location of showers/t-storms as
they remain west of Fargo-Grand Forks-Roseau currently.
Watching area of showers and storms move north out of South
Dakota into SE ND and most models do have a higher pop toward
12z in SE ND likely from this. Storms will remain below severe
levels early this morning.

UPDATE
Issued at 1138 PM CDT Tue Jun 2 2026

Instability has waned considerably over this FA. Therefore,
severe thunderstorm watch #270 was allowed to expire on time at
10 PM CDT. However, there remains some instability and when
combined with a strengthening low level jet, sub severe
thunderstorms will continue overnight. This is evident over the
past hour as radar returns have been increasing on the nose of
the jet across the Devils Lake Basin back into central ND. It
should be noted that due to the meager instability and a lack of
shear, these storms are expected to remain sub severe.

Attention now turns to Wednesdays severe thunderstorm
potential. Incoming 0z CAMs show a wide variety of scenarios at
this time. Many of these CAMs are failing to produce the
current, ongoing sub severe convection across and to our west.
Therefore, predictability in how Wednesday plays out remains
low, and eventual severe coverage will hinge on how quickly
overnight convection clears allowing instability to build back
in, where/if boundaries are left over etc. These variables will
determine severe weather coverage and magnitude of threats
Wednesday afternoon and evening

UPDATE
Issued at 925 PM CDT Tue Jun 2 2026

Isolated strong to severe thunderstorms continue this evening,
with the strongest storms moving across Griggs and into Steele
and eventually Grand Forks County. At this time, storms are
struggling to maintain organization, but still have enough
instability and shear to produce occasional severe wind gusts.
As such, the severe thunderstorm watch has been extended to
include Grand Forks County, Griggs County, and Traill County.
Additionally, heavy rain is training across parts of Pembina
and Walsh Counties.

&&

.DISCUSSION...
Issued at 256 PM CDT Tue Jun 2 2026

...Synopsis...

Southwesterly flow aloft with weak embedded shortwaves moving
through the Northern Plains will continue through tonight and
tomorrow, with the upper low moving every slowly across southern
Canada. South to southeasterly winds will continue through
tonight, then the surface trough axis will push into the CWA by
tomorrow night. The rest of this afternoon and evening looks to
remain active, with another round tomorrow. The upper system
finally starts to pull eastward on Thursday. A weak shortwave on
Friday, but then upper ridging builds into the Plains and
Midwest over the weekend. Warmer than average temperatures
should return. Southwesterly flow aloft again for the first part
of next week, so warm temperatures will continue and chances for
a more active convective pattern increase. Devil is in the
details.

...Severe potential in northeastern ND tonight...

Southeasterly winds have brought dew points into the low 60s
across many locations in eastern ND, and with mostly sunny skies
temperatures have climbed into the 80s. A fair amount of cumulus
extending from the James River Valley up into the Devils Lake
Basin. SPC mesoanalysis page has 2500 J/kg of ML CAPE, and even
higher surface based values. Deep layer bulk shear is pretty
weak south of Highway 2, but around 35 to 40 kts was enough to
get a few isolated supercells going that have been moving off
into Canada. The main trough axis and cold front are still well
to our west, with some modest convection so far. Many of the
CAMs have convective intensity in that area increasing in the
next few hours, which fits the front moving into the region of
high instability. The storms out west should become linear as
they move into our western counties later this evening. Damaging
winds and hail will be the main threat, but will have to watch
the 0-3km shear in case the line become perpendicular to the
shear vector and get a brief tornado spin-up. Heavy rain could
be an issue as we head into tonight and early tomorrow, as there
will be some training as the upper flow lines up nearly parallel
to the surface boundary. With 1.2 inches of PWATs, backbuilding
storms could become a problem even with our recent fairly dry
conditions.

...Severe potential on Wednesday...

Weakening showers and thunderstorms will be ongoing tomorrow
morning near the Red River, so that may have a bit of an impact
on how things develop tomorrow afternoon. Some ensemble members
have CAPE approaching 2000 J/kg in southeastern ND, and deep
layer bulk shear should be a bit better further south than today
with 30-40 kts. CIPS and machine learning both have some 15
percent probabilities of severe impacts. HREF probabilities for
updraft helicity tracks have a bullseye over SD, but over 70
percent chance for 4 hour max UH tracks nosing into Ransom and
Sargent counties. Main threat will be in southeastern ND into
the southern and central RRV south of Highway 2. Large hail over
2 inches will be possible, but can`t rule out a tornado spin up
or some damaging wind.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 714 AM CDT Wed Jun 3 2026

Main issue thru tonight is coverage of showers and thunderstorms
at each of the TAF sites.  Timing of these at any one site is
near impossible so combo of using prob30, VCTS and predominate
such as this morning in DVL. Winds predominately south to
southeast 10 to 20 kts, but usual variability near storms.
Ceilings so far remain VFR 5000 ft agl and higher. Short term
models do want to lower ceilings thru the day and evening into
MVFR range in the RRV and MN TAF sites. Highly uncertain of that
but did go with lowering ceilings esp in MN tonight.

&&

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

&&

$$

UPDATE...Lynch/Rafferty/Riddle
DISCUSSION...JR
AVIATION...Riddle