193
FXUS63 KABR 241138
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
638 AM CDT Fri Apr 24 2026

.KEY MESSAGES...

- Seasonal to slightly below normal temperatures are expected
  from today through the middle of next week. Highs are
  expected to be in the upper 40s to 50s through that period.

- System Sunday through Monday brings moisture to a widespread
  area. Chances of seeing an inch of rain through Monday ranges
  from 40 to 75 percent, increasing from west to east across
  the forecast area.

&&

.UPDATE...
Issued at 635 AM CDT Fri Apr 24 2026

See below for an aviation forecast discussion for the 12Z TAFs.

&&

.DISCUSSION...
Issued at 210 AM CDT Fri Apr 24 2026

Monitoring some showers moving from western South Dakota into
central South Dakota and the Aberdeen forecast area early this
morning. Temperatures will be just above freezing this morning over
central and north central South Dakota, but generally expecting a
deep enough near-surface above freezing layer to melt any falling
snow. However, The near-surface layer isn`t be fully saturated, so
evaporative cooling will push temperatures closer to the wet-bulb,
increasing the chances of freezing temperatures near the surface
supporting snow. Regardless of precipitation type, these showers are
expected to deteriorate shortly after entering the Aberdeen forecast
area this morning, and little to no accumulation is expected.

Rain chances will return this afternoon and stick around through
Saturday, mainly over central and northeastern South Dakota, as well
as western Minnesota. A bit better saturation through the profile as
well as temperatures above freezing through the night (where precip
is expected) means precipitation will have a bit easier time
reaching the surface as rain. Generally expecting one to two tenths
of an inch of rain through Saturday, with only a stray rumble of
thunder or two possible.

The main focus of the forecast is the upcoming long-duration rain
coming Sunday into Monday. A shortwave aloft will help develop
precipitation on the north side of a low pressure center and bring
some moisture into the Aberdeen forecast area. Once again, rumbles
of thunder may be few and far between with this system. Ensemble
median rainfall totals Sunday through Monday night currently show
about 1"-1.5" for nearly the entire forecast area at this point (the
exception being north central South Dakota at around 0.75"-1" at
this point). Ensemble spread is still quite high however, and NBM
25th/75th spread reaches over an inch over the James River Valley,
so there`s still quite a bit of room for refinement with future
forecasts. At this point, highest probability (around 75%) to see an
inch is over northeastern South Dakota and western Minnesota,
decreasing to around 40-50% moving west into central and north
central South Dakota. Overnight lows will approach freezing,
particularly late Monday night into early Tuesday morning. Snow will
be possible as a precipitation type, but little to no snowfall
accumulation is expected.

Behind the passage of the low pressure center to the south,
northerly winds will increase, peaking on Monday afternoon. A low-
level jet overhead mixing to the surface will be the source of these
winds, although there is a bit of a discrepancy between models as to
the strength of this jet. Specifically, the GEFS resolves a bit
lower (about 5 to 10 knots) of a jet than the Euro and Canadian
ensembles. The latter two ensembles sit just shy of 40 knots at
850mb, which sits near Wind Advisory criteria when those gusts are
mixed to the surface. Latest NBM guidance shows a roughly 20-40%
chance of reaching 45 mile per hour gusts at the surface Monday
afternoon, mainly west of the James River Valley.

For next week, ensemble clusters show a fair degree of confidence in
the upper-level pattern remaining consistent through the week: An
upper-level trough with the base over the Midwest/Great Lakes
region. The cold air advection aloft will help to regulate
temperatures, keeping the forecast area normal to near-normal
through mid-week. This setup is not expected to be very conducive to
precipitation, and little is currently expected mid-week beyond some
stray 20% PoPs over central South Dakota at times.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 635 AM CDT Fri Apr 24 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will continue at KMBG and KABR over the next 24
hours. At KPIR/KATY there may be some MVFR cigs happening later
tonight after 00Z. There may be a few sprinkles/very light rain
showers around during the first half of today at KMBG and KPIR.
But, rain chances look to really start ramping up by early this
evening out in the KPIR area, before spreading north and east
overnight into Saturday at KABR and KATY.

&&

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

&&

$$

UPDATE...10
DISCUSSION...BC
AVIATION...10