260
FXUS63 KABR 130723
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
223 AM CDT Mon Oct 13 2025

.KEY MESSAGES...

- Temperatures will fall into the low to mid 30s this morning
  over central SD, with frost development along and west of the
  James River. Freeze conditions are expected over north central
  SD through mid morning.

- There is a 50-70% chance of rain late tonight through the day
  Tuesday. Areas south of U.S. Highway 212 have a 40% chance of
  receiving 0.25" of rain or more.

- There is a 20-40% chance of light rain Wednesday (accumulations
  of a few hundredths) before chances increase to 50-80%
  Thursday. Heaviest rainfall is expected in central SD with a 40
  to 60% chance of more than a half inch.

&&

.SHORT TERM /TODAY THROUGH TUESDAY AFTERNOON/...
Issued at 222 AM CDT Mon Oct 13 2025

The surface low and cold front that brought the gusty west-northwest
winds yesterday continues to depart the area, allowing a high
pressure ridge to move into western SD (from a high in Alberta).
This will allow winds to diminish through the early morning hours
today. That will be a key factor in allowing temperatures to
continue to drop this morning under clear skies. As of 2am, areas
that have seen winds drop off in north central SD are seeing
temperatures in the low 30s. Thus, the existing freeze warning
looking to be in good shape. Wouldn`t surprise me to see some areas
bordering the freeze warning (in the frost advisory) to see temps
fall towards freezing for a couple hours this morning. One final
thing of note, there is an area of stratus over ND that has been
attempting to slide to the south-southeast with time. With the low
level winds turning more northwest-northerly through the morning,
could see them trying to reach northern SD, but confidence is low at
this time (models limited on the extent of that moisture making it
here).

The surface high pressure ridge will continue to move east across
the Dakotas today, leading to light winds and a sunny sky (at least
for the first half of the day). The sun will help offset the cooler
air aloft and produce highs in the mid-upper 50s. Will see
increasing high clouds this afternoon from southwest to northeast,
which will continue to thicken through the evening hours. This is
ahead of the approaching shortwave and mid level warm air advection
that will lead to light showers late tonight and into Tuesday. The
increasing clouds will limit the temperature fall tonight and keep
any frost potential to the northeast of the area. As for the precip
tonight into Tuesday, the initial push of precip will be running
into the lingering dry air from the high as it moves in tonight. But
the persistent 850-700mb southwesterly flow will continue to
reinforce the WAA/moisture and lead to the potential for light
showers into Tuesday (especially with the additional shortwave
help). While chances are good across the entire area for measurable
rain (50-80% on Tuesday, lowest north central), the southeast
half/third of SD will have the best chances for 24hr/event
accumulations over 0.1" and 0.25" (60-70% and 40-60% respectively).
Like the last event, seeing QPF differences in the EC-Ens/GEFS, with
the EC-Ens mean being about twice the amount of the GEFS. Finally,
with the clouds and rain showers tomorrow, expect temps to be in the
upper 40s and lower 50s, which will be 10-15 degrees below normal.

&&

.LONG TERM /TUESDAY EVENING THROUGH SUNDAY/...
Issued at 222 AM CDT Mon Oct 13 2025

The main story for the long term will be rain chances Wednesday and
Thursday. Starting Tuesday night, we are under westerly to
southwesterly upper level flow with a trough off to our west and a
low over California. This low will ride the downwind side of the
trough and move northeast across our area through the day Thursday
before moving into Canada. Models are in good agreement on low track
and timing for this event. The lower level low moves across the
region Thursday and looks to be out by Friday morning. A shortwave
moves across the area Saturday, projected south from the Thursday
low as it moves across southern Manitoba into Ontario.

Showers move out Tuesday night before we get a strong push of WAA
Wednesday that combines with some deep moisture coming up from the
Gulf to pop off some light rain showers ahead of the main event
Thursday. These showers look to impact most of the forecast area but
QPF amounts look to be a couple hundredths at most. Models are
showing that the heaviest precipitation for Thursday will be over
central and north central SD. The NBM has the chance of more than a
quarter of an inch in 24 hours ending Thursday evening between 50
and 70% along and west of a line from Eureka to Pierre. The chance
of more than a half inch in the same 24 hours is around 40 to 60%
west river.

We stay in east to southeasterly winds Wednesday and Thursday for
the most part as most of the forecast area stays on the eastern side
of the low. This will keep up the WAA through the event, bringing
highs on Wednesday into the 60s and into the 70s potentially on
Thursday. Once the cold front moves across the area late Thursday
and into early Friday morning, winds will become more westerly and
bring in a little CAA which will cool our highs slightly, looks like
back into the 50s to 60s for the weekend. Speaking of winds, nothing
too exciting happening there other than Saturday afternoon with some
strong CAA with that shortwave that could help mix some gusts of 25-
30 mph down to the surface mainly west river but there could also be
some isolated gusts around the Sisseton Hills.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1224 AM CDT Mon Oct 13 2025

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are forecast through the TAF period.


&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Freeze Warning until 10 AM CDT /9 AM MDT/ this morning for
     SDZ003-004-015.

     Frost Advisory until 10 AM CDT /9 AM MDT/ this morning for
     SDZ005-006-009-010-016>018-033>037-045-048-051.

MN...None.
&&

$$

SHORT TERM...SRF
LONG TERM...13
AVIATION...TMT