778
FXUS63 KABR 121121 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
621 AM CDT Sun Oct 12 2025

.KEY MESSAGES...

- Light rain continues this morning ahead of a cold front and then
  later this evening along/behind the front. Probability of
  rainfall over half an inch is between 40 and 60%, highest along
  the ND/SD border east of the James River.

- Winds will continue to gust to 30 and 40 mph with some gusts
closer to 45 mph in north central SD this afternoon.

- Temperatures will fall into the low to mid 30s Monday morning
  around and west of the Missouri River. This may lead to some
  frost formation in north central SD.

&&

.UPDATE...
Issued at 621 AM CDT Sun Oct 12 2025

Updated for 12Z Aviation Discussion below.

&&

.SHORT TERM /TODAY THROUGH MONDAY AFTERNOON/...
Issued at 214 AM CDT Sun Oct 12 2025

As of 2 AM CDT, showers are ongoing across northeastern SD and west
central MN. These showers are expected to dissipate quickly this
morning. Winds right now are out of the south to southeast between
10 and 20 mph with some gusts of 25-30 and a few isolated stronger
gusts around the Sisseton Hills. Temperatures around the area are in
the upper 50s to low 60s.

This morning we are in southwesterly flow aloft ahead of the
incoming upper level trough. At the surface, a cold front will make
its way west to east across the forecast area today bringing winds
around to the west to northwest. Strong wind gusts of 30-40 mph are
expected to continue through the day with a wind advisory remaining
in effect for Corson and Dewey counties where winds could gust up to
45 mph. The NBM is showing about a 75% chance for gusts above 40 mph
in this area. East of the James River, the chance of gusts higher
than 35 mph is around 40-60%, and closer to 80% over the Sisseton
Hills this morning, decreasing through the afternoon. On the
precipitation side of things, NBM has increased its expected
rainfall totals today, now the chance of more than half an inch in
24 hours is between 40-60% along the ND/SD border east of the James
River, through this evening. This will come in the form of some
light showers early this morning, most likely done by 7 AM CDT and
some showers along and behind the front this evening, that CAMs are
showing mainly after 5 PM CDT.

Temperatures are going to be a bit of a question across northeastern
SD today with the timing of the cold front and some stratus clouds.
If the clouds move in we might not get too much sun during the
morning hours before the front moves in, and if the front moves in
faster then we will get some pretty strong CAA and won`t get as
warm. If neither of these solutions happen, then the northeast has
the potential to get into the mid to upper 70s today, or about 15-20
degrees above normal. In any event, the air behind today`s cold
front is about 10 degrees cooler (850mb temps go from around 15
degrees C to about 5 degrees C). The result of this will be a much
cooler night with the potential for some frost or freeze across
central SD where overnight lows are expected to drop into the low to
mid 30s. The uncertainty with this lies in winds speeds, if they
will die down enough and soon enough to allow frost formation. This
cooler air is expected to last through the end of the short term,
resulting in highs on Monday about 5-10 degrees below normal.

&&

.LONG TERM /MONDAY EVENING THROUGH SATURDAY/...
Issued at 214 AM CDT Sun Oct 12 2025

Limited weather impacts for the long term forecast, as we`ll see
temperatures moderating back towards normal to slightly above normal
values for the middle of the week as an upper level ridge slides
east of the area. The upper trough in the western CONUS will then
shift east for the second half of the work week and slide another
surface low northeast across the northern Plains. The best rain
chances (40-60%) will be in the Wednesday-Thursday period as that
low moves through.

Continuing to monitor the potential for frost over northern SD on
Monday night as the surface high departs. But the window continues
to look narrow for the proper conditions to line up. This is due to
the increasing mid-high clouds streaming in Monday evening and
continuing through the night. So thinking the coldest temps (upper
30s) will be in the evening with the initial clear skies and then
steady out or even slowly rise during the night.

Finally for rain chances this week. First wave will be on late
Monday night into Tuesday and associated with the mid level warm air
advection and a shortwave lifting northeast through the area under
the southwesterly flow aloft. Accumulations don`t look to be
anything too impressive, with a 30-50% chance of accumulations over a
tenth of an inch in the southeast half of SD. Next wave will be Wed-
Thursday, as the previously mentioned upper trough and low move
through the area. Best precip chances will be in ND, but even
northern SD has a 40-60% chance of a quarter of an inch of rain in a
24hr period. Do expect some gustier winds on Wed/Thurs (25-40mph),
but right now the probability of advisory level gusts (45mph) is
below 50%.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 621 AM CDT Sun Oct 12 2025

Terminals KABR,KATY,KPIR,KMBG

VFR conditions prevail for the TAF period. A cold front will move
eastward through the area today bringing winds around to the west-
northwest and continuing gusts of 25 to 35 kts for all sites through
this evening with some low level wind shear over KABR and KATY this
morning.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Wind Advisory from 11 AM this morning to 7 PM MDT this evening
     for SDZ003-015.

MN...None.
&&

$$

UPDATE...SRF
SHORT TERM...13
LONG TERM...SRF
AVIATION...13