Grand Forks AFB, North Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

755
FXUS63 KFGF 261847
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
147 PM CDT Thu Jun 26 2025

.KEY MESSAGES...

- There is a 2 out of 5 risk for severe thunderstorm chances
  late Friday afternoon into Saturday.

&&

.UPDATE...
Issued at 136 PM CDT Thu Jun 26 2025

Scattered showers continue along and south of the I-94 corridor.
Overall amounts will be light, with most locations seeing up to
a tenth or two of rainfall. This is in part due to dry air near
the surface limiting amount of rain from reaching the ground, as
noted by area surface RH values below 80% except under highest
radar reflectivities, as well as overall weak nature of forcing
and absence of instability.

As this weak wave moves northeast into northern MN, light
showers and sprinkles will pull eastward more into west-central
MN toward north-central MN. Again still very light amounts. No
lightning is expected with this activity.

UPDATE
Issued at 729 AM CDT Thu Jun 26 2025

Tweeked sky cover some as a clearer area remains from Grand
Forks to Baudette with sunshine. Mid and high clouds will move
in but slowed it down. In far SE ND radar returns indicate
sprinkles or very light rain showers increasing as they move out
of SD. Did tweek pops some a bit northward to account for very
light rain showers this morning up to Valley City-Fargo.

&&

.DISCUSSION...
Issued at 343 AM CDT Thu Jun 26 2025

...Synopsis...

Dry across the forecast area tonight, much drier than what was
forecast 24 hours ago. There is a short wave moving northeast
south central South Dakota and Nebraska northeast into central
MN this afternoon. A new area of rain showers and t-storms will
be with this wave, with the far south getting the far north edge
showers. The heavier rain with this wave does look to fall more
in far southern MN with only light amounts (mostly less than
0.10) in our south fcst area. Fargo-Bemidji and north dry today
but rather cloudy, though some sunny breaks at times. There is
expanding MVFR and IFR cloud deck that will be over much of the
area this morning into the aftn....will have to see how far
north the MVFR ceilings get but they may reach most areas except
far north and northeast fcst area. With the cloud cover temps
today will remain below normal.

Some clearing tonight, esp north, but with west-southwest flow
at 500 mb likely at least some  mid/high clouds remain.

Line of thunderstorms is forecast to form from north of Regina
into northeast Montana late today and move into far NW ND and
western Manitoba before likely dissipating.

...Friday and Saturday severe storm chances...

There are differences, sometimes pretty big, in terms of
instability and t-storm development and coverage Friday
aftn/night. Many short term CAM models do keep some light shower
activity remaining in SW Manitoba and NW ND thru the morning
with cloud cover limiting heating. CAMs in particular show this
with NAMnest, HRRR, NSSL CAMs, really backing off sfc and mean
layer CAPE esp in how far north it gets Friday afternoon. HRRR
in particular keeps temps cooler in north central ND into
Manitoba with mid 70s to low 80s and dew pts low 60s vs global
model GFS wants to bring up near 70 dew pts into central ND by
00z. Thus GFS is more unstable with surface CAPE values over
3000 j/kg into SW Manitoba, vs CAMs showing more like 2100 j/kg
into SW Manitoba. Idea thought yesterday of a complex forming
in SW Manitoba and moving southeast may still play out or it is
possible the complex forms more in central ND and moves
southeast more into SD as some CAMs indicate. SPC discussion
agrees that initially supercell in central ND with 0-6 km shear
35-40 kts, ample enough, then growth upscale into a complex, but
where that is and 850 mb low level jet seems a bit weaker again
around 30 kts into E ND/WC MN after 06z Sat, so unsure of
severity at that time. Tornado is possible in central ND but
more wind or hail threat in E ND, but some CAMS have limited
that.

So this means the confidence in how severe weather plays out
late Friday is lower than what it looked like 24 hours. SPC did
remove the sig severe for wind it had 24 years yesterday for
Friday but did keep hatched for hail in south central ND into
north central SD. 2% TOR also in central ND...and some NSSL cams
are slower with east progression Friday aftn of boundary keeping
supercell threat west of DVL. So lower confidence in degree of
severe storms, but threat remains.

Saturday does appear to have more instability as dew pts will be
higher mid 60s to low-mid 70s with mid 70s focused in E
SD/southwest and west central MN in the aftn. Sfc CAPE in those
areas of higher dew points are very high 4000-5000+ j/kg
centered more in far SE ND into WC MN and south. It would appear
that the weak sfc boundary, wind shift will lay somewhere across
north central, west central MN into northeast SD and that is
where a bit higher severe risk is located. SPC Day 3 has slight
risk in those areas which seem reasonable.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 136 PM CDT Thu Jun 26 2025

Area of IFR to MVFR ceilings will continue at TAF sites like
KFAR and KBJI through at least 15Z. There is a medium chance
for additional IFR to MVFR ceilings at other sites between
06Z-15Z, in addition to low chance for dense fog at KDVL, KFAR,
and KGFK. Chose to leave the fog out of TAFs for now given low
confidence in its occurrence over these areas.

Otherwise, lighter winds under 10kt will prevail, excluding
KBJI where winds between 10-20kt out of the northeast will
prevail through 00Z.

&&

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

&&

$$

UPDATE...CJ/Riddle
DISCUSSION...Riddle
AVIATION...CJ