Casselton, North Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

574
FXUS63 KFGF 101935
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
235 PM CDT Tue Jun 10 2025

.KEY MESSAGES...

- Rain south of Valley City to Wadena Thursday/Friday

- Warmer late weekend into next week with increasing rain chances

&&

.DISCUSSION...
Issued at 235 PM CDT Tue Jun 10 2025

...Synopsis...

What was advertised to be the warmest day is certainly not under-
performing with highs in the central Red River Valley already
hitting the mid 80s (seeing a couple stations in Cass and Traill hit
87 so far). This stronger that expected heating can likely be
attributed to western valley downslope to the south of surface low
located near the Grafton area along with building thermal ridging in
the sfc to 700 layer. Overall highs climbing near 90 in the central
Valley with the rest of the area topping out in the low to mid 80s.
Despite these warmer that expected temps the heat risk remains low
with heat indicies only in the mid 80s and wet-bulb temps in the mid
60s. Overall the main change to regional forecast is slightly higher
chances for some storms to roll east across northern portions of
South Dakota this evening/tonight though likely still staying south
of our area as the follow the instability axis along and south of
the state border. As thermal ridging continues to build a shortwave
will traverse the Dakotas/Minnesota Thursday/Friday bring rain
chances to our south with zonal flow prevailing through the weekend
before more rain chances to kick off next week.

- Cap Bust

As the 850 thermal ridge axis is pushed southeast this afternoon by
a cold front steepening mid level lapse rates across South Dakota
will result in MUCAPE >1500 J/kg mainly in Aberdeen`s area
through up to 1000 J/kg could still overlap with shear >40kts in
western Minnesota in our far southeast providing enough juice
to support any storms working in from the west. Overall cams
still seem very sheepish on storms forming likely due to rising
heights and the present ridging but a few do track some east
from what is likely orographic forced in the northern Black
Hills vicinity. Thinking that if anything does 1) initiate and
2) sustain itself east they would be capable of hail 1.75" or
greater with gusts over 60mph but the general lack of any signal
from cams paints serious doubts towards the true convective
threat. Would pessimistically put the southern FGF area in a <2%
threat for any severe tonight.

- Thursday/Friday Rain

As a shortwave traverses the zonal flow regime Thursday and Friday a
Baroclinic zone across the northern plains will provide a focused
area of ascent with heavy rain falling across eastern South Dakota
and southern Minnesota where there is >60% chance for an inch or
more. While the the heaviest rain will very likley fall to our south
with only a 20% chance for > 1" in areas south of Valley city to
Wadena there is still good odd of 0.25 to 0.50" along the state
border north towards Fargo with amounts tapering off quickly north
of there as dry air entrainment becomes an issue on the north side.
No severe threat is expected to accompany this rain but some thunder
in the south Thursday night is possible with MUCAPE around 100-
200j/kg. A more southern track would hamper rain amounts and lead to
minimal thunder chances. Friday appears to be the coldest day this
week with highs only in the 60s mainly due to the ongoing rain and
cloud cover. Highs otherwise in the 70s through Saturday.

- Warmer and Wetter

Zonal flow looks to give way to pacific northwest troughing though
the signal remains weak with embedded waves traversing the area by
the end of the weekend leading to increasing rain chances. Temps
warming back into the upper 70s and low 80s Sunday and beyond with
daily thunderstorm chances. Severe potential while certainly there
given climatology and the general pattern but the true magnitude of
the threat remains unknown given temporal and spatial differences
from ensemble based guidance. Will note that some of the ML sources
area indicating a relatively higher threat compared to recent for
Sunday and Monday though the details still very much need to be
ironed out before putting real confidence in any of it.&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1215 PM CDT Tue Jun 10 2025

VFR skies prevailing with winds gradually shifting S to NW this
afternoon as gusts hit 20-25kts Smoke is still being reported by
the observers at GFK and FAR through vis reductions area only
being noted at GFK. Have kept the mention of smoke in the taf
through the mid afternoon but confidence on timing and impacts
is low.

&&

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

&&

$$

DISCUSSION...TT
AVIATION...TT