473
FXUS63 KABR 182315
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
515 PM CST Tue Nov 18 2025

.KEY MESSAGES...

- There is a 20% chance of light rain over portions of north central
SD overnight into Wednesday morning. Precipitation amounts of less
than 0.05" can be expected.

- Expect patchy fog over the Prairie Coteau, the higher elevated of
northeastern SD, overnight into mid morning Wednesday. Visibility is
forecast to be around a mile or greater, with localized dense fog
possible. The lowest visibility will be near sunrise Wednesday.

- High temperatures will be in the 40s and 50s through next Tuesday,
which is around 5 to 10 degrees above normal.

&&

.UPDATE...
Issued at 512 PM CST Tue Nov 18 2025

Layer of stratus continues to creep northwards. See below for an
update to the aviation discussion...

&&

.DISCUSSION...
Issued at 242 PM CST Tue Nov 18 2025

Little in the way of significant weather is currently expected over
the next several days. However, there are some features like light
rain, fog, and above normal temperatures to discuss. The main
deviation from seasonal norms is the temperatures. This is backed up
by the Ensemble Situational Awareness ECMWF Extreme forecast index
(EFI), which highlights the slightly above normal temperatures
across the Northern Plains. High temperatures will be in the 40s and
50s through next Tuesday, which is around 5 to 10 degrees above
normal.

Rainfall amounts of 0.25 to around 0.80 fell Monday afternoon
through early Tuesday morning, mainly south of a line from around
Pierre through Redfield and Watertown. Fall is typically our most
foggy time of the year, and with the additional low level moisture
and cool temperatures fog will be most likely over the Prairie Coteau
overnight into Wednesday morning. Visibility is forecast to be
around a mile or greater, with localized dense fog possible. The
probability of visibilities under 1 mile is around 15% or less. The
lowest visibilities will be near sunrise Wednesday.

Other than a 20 percent chance of light rain of less than 0.05
inches over north central South Dakota overnight into Wednesday
morning as a weak 500mb wave moves across the area, dry weather is
forecast through at least Tuesday of next week.

Taking a look at the latest surface map, a ridge of high pressure
dominates our weather, stretching from the main high over Lake
Superior and Upper Michigan. There is yet another elongated area of
low pressure near the Rockies. The weak area of low pressure
currently over central MT and northern WY will shift over the Black
Hills by 12Z Wednesday and slowly shift east across SD through 06Z
Thursday and across MN Thursday morning. Dry weather will accompany
its passage, with clouds and relatively light shifting winds being
the main result.

High pressure will then build in to the Dakotas Thursday morning
through sometime Friday. There is some uncertainty due to the
stronger system shifting across the Central/Southern Plains on
Friday. Slight timing differences will have little impact to our
sensible weather for the end of the work week. Highs will stay
mainly in the mid 40s to mid 50 through Tuesday of next week.
However, the 25-75th percentiles for temperatures to spread out to
be around 10 degrees from Monday on, leading to a lower confidence
at that time range. As noted on the previous discussion, after
lighter winds, a period of stronger wind will be possible Monday
night on with gusts mainly in the 20-30mph range. This will continue
to be fine tuned as that time nears.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 512 PM CST Tue Nov 18 2025

Terminals KABR,KATY,KPIR,KMBG

Layer of MVFR stratus impacting KMBG/KPIR/KABR for the foreseeable
future, though possibly shifting out of the KPIR terminal later.
Fog where its clear, primarily around KATY also expected.

&&

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

$$

UPDATE...07
DISCUSSION...06
AVIATION...07