131
FXUS63 KABR 131905
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
205 PM CDT Mon Oct 13 2025

.KEY MESSAGES...

- There is a 50-70% chance of rain late tonight through the day
Tuesday. Areas south of U.S. Highway 212 have a 60% chance of
receiving 0.10" 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 75% chance of
0.25" or more.

&&

.DISCUSSION...
Issued at 203 PM CDT Mon Oct 13 2025

The surface ridge that dominated our area is shifting northeast,
from the center of high pressure over southern Saskatchewan. The
main concern over the next 24 hours is light rain moving in from the
southwest as a lee trough organizes at the surface and energy moves
in on the southwesterly flow at 500mb. The initial concern will be
how much dry air will remain from the exiting surface high. Also,
forecast solutions have shifted some of the precipitation to our
south compared to 24 hours ago. There is still at least a 60% chance
of 0.10" of rain or more southeast of a line from Pierre to Aberdeen
to Sisseton. Little to no accumulation is expected over north
central SD. Southeasterly winds will be on the return Tuesday, with
gusts 25-30mph over central SD. Cooler air will remain overhead,
with 850mb temperatures of 4-9C by late Tuesday afternoon. Plenty of
clouds and light rain should keep high temperatures in the upper 40s
to low 50s.

Any break from precipitation will be short lived (or at least
reduced) Tuesday night through Wednesday. The surface trough to our
west will shift across southwestern SD to northeastern CO by 06Z
Thursday, while the 500mb low ejects northeast across UT through MT
both increasing the moisture plume into SD/western MN. The EFI shift
of tails highlights the potential for well above normal temperatures
Thursday morning, which look to be in the 49-56F. Normal lows this
time of year are in the mid to upper 30s. Highs Thursday should
briefly jump back into the upper 60s to low 70s. The slow moving
500mb low will shift across ND by midday Friday, becoming stacked
with the surface low as it wraps up. Relative humidity will be high,
at or above 60% each afternoon Tuesday through Thursday. The focus
for the highest precipitation for the second half of the work week
will be central SD, with a 75% chance of 0.25" or greater over north
central SD while around 40% elsewhere in the forecast area. At this
time most of the precipitation looks to fall early Thursday morning
through Thursday evening. The SPC Day 3/Thursday outlook highlights
our far southwestern counties in the Marginal Risk, and a southern
extent to this are looks reasonable at this time.

Frost of potential freeze conditions will return Saturday morning,
Sunday morning, and again Monday morning. The surface ridge will be
mainly overhead on Sunday, with no distinctly light winds to
accompany any of those mornings. Still, the lowest temperatures are
forecast Sunday morning, with confidence decreasing as the 25-75th
percentiles for temperature increase Sunday on. There is a 50%
chance of lows Sunday morning being at or below 32F, particularly
over much of Corson and Campbell Counties through western Dewey
Counties. The chance of 36F or below increases to 50% or greater
over all but our west central MN Counties.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1230 PM CDT Mon Oct 13 2025

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will likely continue over the next 24 hours. Light
rain moving in from the southwest could bring MVFR ceilings or
visibilities to PIR by or shortly after 18Z Tuesday.


&&

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

$$

DISCUSSION...06
AVIATION...06