650
FXUS63 KFGF 170246
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
946 PM CDT Wed Apr 16 2025

.KEY MESSAGES...

- The probability for widespread hazardous weather is low for
  the next 7 days.

&&

.UPDATE...
Issued at 944 PM CDT Wed Apr 16 2025

Showers and thunderstorms have developed along a line west of
the Sheyenne River Valley. Instability is just enough to produce
a few lightning strikes. These are moving very slowly and likely
not all the rain drops are making it to the ground, but you
could see some flashes in the distance. Impacts will be
primarily tied to lightning and should remain fairly minor given
the sparse nature of the lightning.

UPDATE
Issued at 618 PM CDT Wed Apr 16 2025

As of 23z, the front is situated on a line from Minot through
Bismarck and is slowly trudging eastward. Wind gusts will
diminish, however expect breezy conditions to continue until the
front approaches. Precipitation-wise, as expected, the radar
returns continue to be virga. Impacts should remain limited this
evening as a result.

&&

.DISCUSSION...
Issued at 228 PM CDT Wed Apr 16 2025

...Synopsis...

Split upper trough will move slowly through western North
America tonight and tomorrow. One main upper low moving from
northern Saskatchewan into Manitoba will help push a cold front
into our CWA. A few sprinkles not out of the question in
northeastern ND this evening as a lead shortwave passes through,
but most of the precipitation will come with the mid level
baroclinic zone tomorrow. Some of the ensemble members are
rather bullish on precipitation amounts thanks to strong
700-850mb frontogenesis, but probabilities of over a half an
inch of liquid are only 10 to 20 percent in spotty areas, and
even a quarter of an inch of rain probs are around 40 percent.
At this point, some light rain seems most likely. Not out of the
question for a few snow flakes to mix in tomorrow morning in the
Devils Lake Basin with HREF showing 50 percent probability.
However, any impacts are very unlikely with METRo roadcasts
keeping our area above freezing.

Still some variation in how the models handle the southern
branch of the split trough this weekend and into Monday. Some
bring its influence and therefore some precipitation into west
central MN, while some do not. NBM has 15-30 POPs in that
period, and see little reason to make changes at this point.
Slightly better agreement on another northern branch shortwave
moving through the Northern Plains on Tuesday, but still a lot
of spread in ensemble members and no clear signal for any
impacts.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 618 PM CDT Wed Apr 16 2025

There will be quite the myriad of aviation impacts, from wind
shear to MVFR ceilings to wind gusts and rain showers.

Starting with the first six hours, wind gusts will remain
through sunset tonight, with continued elevated sustained winds
between 10-15 knots thereafter. A front will push through this
evening and overnight from west to east, although this front has
been slowgoing on getting its way through. As of 23z, the rough
front location is situated between MOT down through BIS. Ahead
of this front, low-level wind shear will develop (or already has
looking at PIREPs) and intensify as we approach sunset. Once the
front pushes closer, speed wind shear should diminish. As this
front comes through, winds will diminish at the surface to
primarily light and variable, then becoming northerly and
intensifying again to 10-15 knots sustained. Gusts should hold
off until after 07z but cannot be ruled out prior to this. Once
a TAF site hits northerly winds, they will stay there for the
remainder of the TAF period. Down-valley winds at GFK and FAR
will push wind gusts to at least 30 knots by the afternoon,
possibly higher.

Ceilings will remain VFR, although virga may be observed at DVL
early this evening. Precipitation chances look to increase as we
approach 12z, combined with ceilings beginning to lower. VFR
ceilings should remain through at least 12z, but will fall to
MVFR by 18z for pretty much all TAF sites outside of DVL
(although DVL may come close to MVFR). There is a signal (a 30%
chance) for IFR ceilings to develop, mainly at FAR and BJI, but
for the most part, ensemble models are trending towards 2000
feet for ceilings.

&&

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

&&

$$

UPDATE...Perroux
DISCUSSION...JR
AVIATION...Perroux