Watertown, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

323
FXUS63 KABR 052343
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
543 PM CST Fri Dec 5 2025

.KEY MESSAGES...

- Snow returns Saturday. 1 to 4 inches of accumulation is
expected, with highest amounts south of Highway 212 in east central
SD.

- There will be periodic lower chances for precipitation (20-40%)
through early next week, as more weak weather systems have the
potential to move through the region.

&&

.UPDATE...
Issued at 543 PM CST Fri Dec 5 2025

The ongoing forecast remains on track, with few changes needed
this evening. The Winter Weather Advisory remains in effect for
9 AM-6 PM Saturday for our 4 south-southwestern counties.

&&

.DISCUSSION...
Issued at 103 PM CST Fri Dec 5 2025

The pattern will remain active through the middle to end of the
upcoming week. The region will mostly stay in an upper trough but
will continue to have numerous shortwaves rotating through the upper-
level flow. These shortwaves will bring periods of light snow and
potentially mixed precipitation through next Thursday.

Most of today`s precipitation has exited the region, however there is
still a mix of light snow and freezing drizzle in west central MN
early this afternoon. Colder air has also backdoored into the
northeast, causing temperatures to fall about 5 degrees since this
morning. Surface low moves through NE on Saturday. This combined
with a shortwave over SD will produce some light snow starting early
in the morning across central SD and moving east through the day. A
Winter Weather Advisory has been issued for portions of east central
SD where higher QPF has pushed farther north in latest model runs.
Generally expecting 2-4 inches south of HWY 212, with lower amounts
farther north and west. Snow showers may linger well into the
evening on the backside of the surface low.

Arctic high pressure builds into eastern SD Saturday night into
Sunday when highs may only be in the single digits east of the James
Valley. Return flow behind the high as well as an upper ridge
building east into the Plains will see temperatures rebound into
Monday as highs climb into the 40s in central SD. The warmer air
Sunday night along with a passing shortwave could result in some
additional light snow. On Tuesday, low pressure remains to the north
with main impacts across ND and MN. Will need to keep an eye on this
one as any southerly drift in the track of the low could
significantly change expectations. Wednesday night into Thursday has
the potential for more warm air advection banding with the low
pressure heading over SD and NE.

From Saturday evening through the end of the period, the over-
arching flow pattern theme remains "positive PNA". Northwest flow is
still lining up transient clipper-like shortwaves over the region,
each one separated from the next by roughly 24 hours.

With the active pattern of low pressure systems working through, the
low level thermal advection pattern will be pretty busy. Weak low
level CAA is happening Saturday night into Sunday morning, but low
level WAA is expected to kick in by late in the day Sunday and
persist into Monday. Warm air is forecast to stick around Monday
night into Tuesday before the next system`s strong cold frontal
passage knocks temperatures back down to near to below normal for
the middle of next week.

The probabilities of seeing a 0.10in or more of water equivalent in
any given 24 hour period in the out periods is low (less than 10
percent). Likewise, the chances of seeing 0.01in or more of freezing
rain/ice accumulation or 3 inches or more of snow are low. That
being said, the clipper system moving through North Dakota into
Minnesota Tuesday/Wednesday will need to be watched closely for any
shifts further south in track/placement, as this system holds the
chance of producing headline-able conditions. But for now, model
output/ensembles are still maintaining that the bulk of this system
will track through the region north of this CWA.

Looking a little bit more closely at the wind potential
Tuesday/Wednesday, it appears that a corridor of fairly strong winds
(off the surface) will be overspreading the CWA while it`s within
the warm sector of the clipper system. Current model progs suggest
that it`s not until at or after 21Z Tuesday that strong winds aloft
will be able to be mixed down to the ground, as that is roughly what
time the system`s cold frontal passage is slated to begin sweeping
through the CWA, first across north central South Dakota, but then
quickly following through central and northeast South Dakota and
west central Minnesota, especially at or after 00Z Wednesday when
strong low level CAA, pressure rises and winds just a half kilometer
off the ground will be working in tandem to present a strong wind
concern. Not too confident about a blowing snow concern, though, if
the CWA has been at or above the freezing mark for nearly 48 hours.
Thinking there may not be much blowable snow left after warm
boundary layer conditions like that.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 543 PM CST Fri Dec 5 2025

Terminals KABR,KATY,KPIR,KMBG

Plenty of MVFR clouds remain, with occasional pockets of VFR
ceilings at both MBG and PIR that may move to ABR by 03Z Saturday.
Otherwise the main concern this period will be light snow with
visibility and ceilings falling to IFR by 15-17Z Saturday at all
of the terminals as low pressure tracks from far southwestern
SD/western NE at 18Z Saturday to southern NE/north central KS by
00Z Sunday. While ceilings are forecast to remain IFR through the
rest of the period, ceilings may improve to MVFR at or a couple
of hours after 22Z at MBG/PIR.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Winter Weather Advisory from 9 AM to 6 PM CST Saturday for
     SDZ018-019-022-023.

MN...None.
&&

$$

UPDATE...06
DISCUSSION...20
AVIATION...06