620
FXUS63 KFGF 231510
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
910 AM CST Sun Feb 23 2025

.KEY MESSAGES...

- Patchy fog will continue this morning, especially from the
  Devils Lake region into the Red River Valley.

- Very mild temperatures are anticipated this week, which will
  continue to erode the snowpack.

&&

.UPDATE...
Issued at 857 AM CST Sun Feb 23 2025

An area of dense fog within the Red River Valley is proving to
be the main forecast challenge.

Latest guidance favors its dissipation by 11 AM CST, with some
guidance offering improvement starting around 9 AM CST;
conversely some guidance lingers dense fog through Noon CST.

The main mechanisms to diminish fog continues to be increasing
winds around mid to late morning along with higher clouds moving
into the area from the west.

UPDATE
Issued at 536 AM CST Sun Feb 23 2025

Fog remains very shallow and patchy so far. It seems to only be
affecting portions of the Devils Lake region eastward toward
Grand Forks and Hallock. Visibilities have been bouncing all
over the place, but as low as a quarter of a mile. Thinking with
increasing winds this morning and the high clouds quickly
moving in, the fog will not last more than another couple of
hours.

&&

.DISCUSSION...
Issued at 254 AM CST Sun Feb 23 2025

...Synopsis...

The 500mb pattern will oscillate from zonal to flat northwest
through Wednesday, then the FA will be on the edge of ridging
centered more over the Rockies. A series of weak shortwaves still
look like they will track through the FA, although with such
warm temperatures, none of these look to be impactful. There are
waves late this afternoon/evening, Monday, Tuesday/Tuesday
night, Wednesday night, and Friday/Friday night.

...Fog this morning...

Mainly clear skies have spread into most of the FA, as the
broken mid level cloud deck has pushed into Minnesota. Wind
speeds are mainly light, which has led to some fog development.
There have been a few spots that have briefly dropped to a
quarter of a mile, but then they rise back up again to the 4 to
6 mile range. Overall, don`t expect the fog to become dense or
very widespread.

...Very mild temperatures this week...

Temperatures continue to look very warm this week, with many
areas reaching the 40s, with some 50s even possible?
There seem to be three areas where temperatures have warmed
more than others, being along the Dakotas border, from Grand
Forks to Grafton, and from Lake Itasca to Bemidji. Will continue
to make manual adjustments to keep these three areas at least 3
to 5 degrees warmer than areas around them.

For this afternoon into tonight, have been watching the
strength of the west winds. If they would be stronger than
expected, some drifting snow could be possible across the
Langdon to Devils Lake area. For most of the day, the regime
looks like warm advection. A trough does pass early tonight,
with some slight cool advection behind it. However, this will be
at night, and model soundings continue to show a pretty decent
inversion. So at this point, am going to stick with winds on the
lower side. This combined with the mild temperatures today and
tonight, should keep any drifting to a minimum.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 857 AM CST Sun Feb 23 2025

This update to AVIATION mainly pertains to KGFK:

Dense fog within the central and northern Red River Valley
continues to hold low confidence in cessation. Latest guidance
favors its dissipation by 17Z/11 AM CST, with some guidance
offering visibility that start to improve around 15Z/9 AM CST;
conversely some guidance lingers dense fog through 18Z/Noon CST.

There were some hints that the earlier cessation timing could
be coming to fruition based on latest trends on the UND Skycam
in Grand Forks and DOT webcam in Emerado, but has re-intensified
since then. Thus, an amendment was made to forecast dense fog
within a TEMPO group between 15Z-16Z, while diminishing fog
around 16Z. This remains to be a low confidence forecast with
respect to VLIFR conditions before 18Z.

Previous AVIATION:
Issued at 536 AM CST Sun Feb 23 2025

The fog will be the main impact this morning, mainly affecting
KGFK. As mentioned above, thinking with increasing winds and the
high clouds moving overhead, it shouldn`t last too long into the
morning. Otherwise, winds will be a little higher today at KDVL,
but not sure how gusty they will get with the SW/W direction.
Model soundings show a decent inversion in place, so still
expect LLWS by late afternoon into tonight.

&&

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

&&

$$

UPDATE...Godon/CJ
DISCUSSION...Godon
AVIATION...Godon/CJ