418
FXUS63 KABR 251120 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
620 AM CDT Sun Oct 25 2026

.KEY MESSAGES...

- Rain chances will become more widespread today through early
  Tuesday. Probabilities of seeing one inch or more range from
  20-50 percent across north central SD to 50-90 percent from
  south central SD into northeast SD and west central MN.

- Snow will mix in with the rain on Monday and Monday night across
  north central SD. Minor accumulations, especially on grassy
  surfaces will be possible. There is a 30-60 percent probability
  of seeing one inch of snow across western Corson County.

&&

.UPDATE...
Issued at 608 AM CDT Sun Oct 25 2026

Updated discussion for the 12Z TAFs below.

&&

.DISCUSSION...
Issued at 255 AM CDT Sun Oct 25 2026

Current conditions early this morning across the forecast feature
partly to mostly cloudy skies and temperatures mainly in the 30s.
Low level cloud cover has been thickening across Nebraska and has
been shifting into far southern SD. Surface high pressure centered
across the Dakotas this morning will have a temporary hold on
weather conditions today across parts of our forecast area. However,
changes are in the works as an upper level low across the Four
Corners region today sends shortwave energy northward across the
Plains. This will aid in an influx of moisture northward into our
southern zones during the morning and midday hours. With the sfc
ridge positioned to our north and northeast, and a dry northeast
fetch into our northern zones, this should keep most of the rainfall
across our south through the first half of the day. BUFKIT soundings
across northeast SD indicates low level dry air persisting through
midday. The lower portion of the atmospheric column begins to
saturate during the afternoon hours when more favorable mid level
dynamics or UVM becomes stronger. CAMs more or less agree on this
scenario with most of the rainfall concentrated to the south through
the morning before becoming more widespread during the course of the
afternoon into this evening. Although temperatures will remain
rather cool today into tonight, p-types across the forecast area
remain mostly liquid per the latest EC ENS p-type meteograms. Models
begin to disperse the widespread precip coverage later tonight into
the overnight hours.

That upper low is progged to shift northeast across the Rockies
tonight and out into the Central and Northern Plains Monday into
Monday night. Another slug of more significant moisture shifts north
into our region. Some of the moisture within this upper low has
eastern Pacific origins from remnants of a tropical system. Some
noteworthy rainfall from this system is expected to fall in parts of
the forecast area. Probabilities of seeing at least 1 inch or more
between today and early Tuesday range from 20-50 percent across
north central SD to 50-90 percent from south central SD into
northeast SD and west central MN. At this point, along and east of a
Pierre to Aberdeen line have at least a 70 percent chance or higher
of seeing that amount of precipitation. Again, the precipitation
type across most of the forecast area will fall as rain per the p-
type meteograms, albeit a chilly rain. However, there are some
caveats to this that could lead to our first bout of snowfall this
season. Timing and placement of the mid and upper low features along
with the temperature profile, specifically the strength and depth of
a warm nose aloft and near sfc temperatures and moisture or lack
thereof in the DGZ will dictate if/when and where snow may occur.
Most favorable areas where these ingredients may all come together
for frozen precip will be across north central SD. P-type meteograms
at MBG indicate a 10-30 percent probability of seeing wet snow
Monday afternoon/evening. Again timing and placement of precip and
temperatures will be key to any accumulation possibility.
Probabilities of seeing 1 inch of accumulation range from 30-60
percent and confined to mainly western Corson County. The intensity
of any falling snow plus ground temperatures will be factors
if and where snow will stick.

This system will exit to our northeast early Tuesday and quickly be
followed up with another upper trough that is currently progged to
take a track more to our northwest from MT into ND. If this
verifies, our area should remain mostly on the dry side around the
middle of the week. Sfc and upper ridging mid to late week should
lead to drier conditions and modifying temperatures at or above
normal for late October.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 608 AM CDT Sun Oct 25 2026

Terminals KABR,KATY,KPIR,KMBG

Ceilings will gradually lower (from south to north) over the
region through the TAF period with MVFR cigs forecast early
this afternoon at KPIR and later on tonight at KATY. KABR/KMBG
should remain in VFR through the TAF period with lowering cigs
to MVFR beyond the forecast time. Rain will track northward
across the region and becoming widespread at all TAF sits this
evening into tonight with a couple rounds of light to moderate
rain through Monday into early Tuesday before finally
diminishing southwest to northeast across the region. Any
heavier rain bands could result in sub VFR/MVFR cigs. There is
a possibility of light snow or a rain/snow mix at KMBG early
Monday morning with better chances of snow to the northwest/west
of KMBG. Little to no accumulations expected at KMBG. Winds
will remain out of the east/northeast and increasing early
Monday morning with gusts of 15-20kts.

&&

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

&&

$$

UPDATE...MMM
DISCUSSION...Vipond
AVIATION...MMM