401
FXUS63 KABR 151013
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
413 AM CST Wed Jan 15 2025

.KEY MESSAGES...

- Mild air is ushered in today on westerly winds with gusts 25 to 40
mph. Warmer temperatures persist into Friday at 10 to 20 degrees
above normal.

- The next arctic blast comes with readings 15 to as much as 30
degrees below normal late Friday into early next week. The arctic
air will bring the potential for morning wind chill values of 30
degrees below zero or colder Sunday into early next week.

&&

.SHORT TERM /TODAY THROUGH THURSDAY AFTERNOON/...
Issued at 412 AM CST Wed Jan 15 2025

Warm air advection is slowly advancing into the region early this
morning as overnight temperatures have already come off their below
zero lows west of the Coteau. Westerly flow up through 850mb on the
southern edge of a sfc trough will help usher in the warmer air
while an 80 kt jet aloft should help enhance mixing. That will mean
westerly winds gusting 25 to 40 mph (highest along the downslope
areas of the Coteau) could make temps in the 30s to lower 40s not
feel quite so warm. Conditions remain breezy through tonight with
northwest flow through the column, but the winds should help keep
lows from bottoming out. Forecast lows are in the upper teens to
lower 20s which carries high NBM uncertainty and may be slightly
ambitious given the 0 to -8C 850mb temps holding on in the northeast
tonight.

By Thursday afternoon, the whole cwa is above 0C at H85 with most
levels showing south to westerly flow. So even with lighter winds
and less mixing, temperatures are expected to remain above normal by
10 to 15 degrees.

&&

.LONG TERM /THURSDAY EVENING THROUGH TUESDAY/...
Issued at 412 AM CST Wed Jan 15 2025

While we start off mild Thursday night, a cold frontal passage
Friday will result in falling temperatures and strong winds. NBM
gusts have increased to closer to 35 to 45mph, a slight uptick from
24 hours ago. That remains fairly close to what NAM BUFKIT profiles
would suggest, though with strong cold advection and 10mb/6 hours
pressure rises, will probably need to add a slight increase to gusts
above that NBM mean in upcoming forecasts. BUFKIT profiles also
support cold advection instability and showers within the post
frontal environment. Guidance coverage continues to be relatively
minimal at this point, and profiles dry out/stabilize about 4-6
hours after frontal passage, however the NBM has overly smoothed out
any mention of snow showers so went ahead and added a 20
percent/slight chance so they will be at least covered despite
overall resulting in only about a dusting.

So the main question thereafter is how cold will it get. The surface
high continues to take a trajectory through the eastern Rockies into
the High Plains, meaning for most of the area there is a perpetual
gradient. Persistent light winds and a lack of consistent snow cover
may temper extremes when it comes to temperatures, but the airmass
continues to run at between 2 and 3 standard deviations below climo.
Current NBM highs are right around zero Sunday/Monday when the core
of coldest air is overhead, with overnight lows of 10 below to 20
below.  We do see some milder temperatures in the wake of the Arctic
airmass, however there is quite a bit of difference on how
deterministic guidance handles the pattern thereafter, and as such
confidence with respect to mid-week temperatures is low. NBM
25th/75th percentiles for highs Tuesday have about a 13 to 18F
difference.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 412 AM CST Wed Jan 15 2025

Terminals KABR,KATY,KPIR,KMBG

Other than some MVFR stratus near KATY this morning, VFR
conditions are expected to prevail through the next 24 hours.
Westerly winds increase by this afternoon with gusts to 30 kts.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&

$$

SHORT TERM...Wise
LONG TERM...Connelly
AVIATION...Wise