442
FXUS63 KFGF 130440
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
1140 PM CDT Wed Jun 12 2024

.KEY MESSAGES...

- Scattered severe thunderstorms this afternoon in northwest
  Minnesota. All hazards possible with up to 2" hail, wind to
  70mph, and isolated tornadoes.

- There is a 15 percent probability of another round of severe
  thunderstorms on Monday.

&&

.UPDATE...
Issued at 1140 PM CDT Wed Jun 12 2024

Last of the thunderstorm activity has moved east of the region
this evening, with a frontal boundary shifting southward through
the Red River Valley. We will be watching the storms up in
southern Manitoba as they shift southward overnight, but severe
weather is not expected.

UPDATE
Issued at 1003 PM CDT Wed Jun 12 2024

Updated to clean up pops with the line of small showers/storms
still moving through the northeast and could see another storm
or two skirt the far north around 06-08Z with the activity
further back to the NW in Manitoba. Adjusted winds some for the
night and sky cover with the northeastern activity. Remainder of
forecast is on track.

Previous update
Issued at 622 PM CDT Wed Jun 12 2024

Strongest storms in west central MN have moved into NE MN and
central MN this evening. We continue to monitor the storms up in
Cavalier, Pembina, and Kittson counties as strong surface
vorticity is noted along with MLCAPE. In southeastern ND we are
starting to loose the heat and instability this evening limiting
further development for that area. Northern MN is currently
seeing the atmosphere stabilize slowly.

&&

.DISCUSSION...
Issued at 344 PM CDT Wed Jun 12 2024

...Synopsis...

Main upper wave still over southern Saskatchewan, with surface
low over the central Red River Valley. Starting to get some
towering cumulus clouds in portions of our CWA, although anvils
have quickly been orphaned. Still, getting some ML CAPE up into
the 1500-2000 J/kg range, and effective shear is around 40 to 50
kts. Special sounding from UND in Grand Forks had fairly dry in
the low layers, and this fits with surface obs that have been
mostly in the 50s on the ND side of the river. This does not
rule out the formation of supercell thunderstorms that could
produce hail 2 inches or larger however, and there will be a
severe thunderstorm watch coming out shortly. Winds up to 70 mph
and even an isolated tornado not out of a question, but
continue to think hail will be the main threat. The cells will
move quickly off into central MN during the later part of the
evening after 00Z.

A second shortwave will be digging into MN during the day
tomorrow, with some additional showers and thunderstorms in the
far north and northwestern portions of the CWA. A few of the
ensemble members have CAPE values of around 1000 J/kg tomorrow
afternoon as this shortwave comes through, but that is well
above the ensemble mean of 500 J/kg. Think we will see some
thunder chances, but at this point think probabilities of severe
will be less than 5 percent.

Upper ridging will move into the Plains then transition to
southwesterly flow for Friday and into the weekend. Some
precipitation chances with weak ridge riding shortwaves, but
predictability is low for any impacts other than rainfall as
destabilization is uncertain and shear is not impressive. Better
shear on Monday as stronger southwesterly flow sets up and a
surface boundary arrives over the Northern Plains. Type of
impacts are still uncertain, but there is a 15 percent chance
for severe storms to develop for the start of the work week.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1140 PM CDT Wed Jun 12 2024

Storms have dissipated across the region this evening, with a
few isolated thunderstorms in southern Manitoba that will shift
southward post 7z. These have a slight potential to affect TVF
and DVL between 7z and 12z. Otherwise, winds will turn toward
the west around sunrise, with gusts reaching 25kts for DVL, TVF,
FAR, and GFK 18z through 02z. Isolated thunderstorm potential in
the mid afternoon through 3z for TVF and BJI.

&&

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

&&

$$

UPDATE...MJB/Spender
DISCUSSION...JR
AVIATION...Spender