474
FXUS63 KABR 270612
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
112 AM CDT Tue Oct 27 2026

.KEY MESSAGES...

- Low clouds and fog, with drizzle possible, will linger over the
region this morning with gradually clearing skies over portions of
central South Dakota through this afternoon and evening.

- Patchy to areas of fog is possible late tonight through early
Wednesday morning. It could be dense at times, especially between
the Missouri and James River with a probability of visibility of
1/4th mile or less at 50 to 80%.

- Rain chances return to the region Wednesday, with the highest
chances of 60-85% James Valley and eastward by the midday through
the afternoon. Weak thunderstorms are possible.

&&

.DISCUSSION...
Issued at 105 AM CDT Tue Oct 27 2026

As of 1am, radar indicates light rain showers mainly along and east
of the James River (with the bulk of it over east central SD) as
temps remain above freezing, in the upper 30s. The wrap around
portion, that we saw as snow earlier, has now moved off into ND/MN,
but there is still the potential for light flurries lingering over
north central to the James River, mainly along the ND/SD border.
Winds are out of the northeast between 10-15 mph with visibilities
down to 5-6SM at KABR and KATY and down to 7SM at KMBG.

CAMs/REFS/NBM overall agree on the last of the precip exiting
NESD/MN by ~12Z or so. By this time, its negatively tilted upper
wave`s axis will be over eastern ND through MN and clipping far NESD
and its nearly stacked surface low hovering over southwestern/south
central MN and SD border. Through the morning this entire system
will continue to track off towards the northeast. However, REFs/NBM
indicates low stratus clouds/fog will be hanging around through much
of the morning before starting to clear out over south central SD
midday or so. These clouds will somewhat clear across central and
potentially portions of NESD/MN this evening through the early parts
of tonight. With these low clouds/moisture, soundings do indicate we
could be dealing with ongoing drizzle (maybe light freezing drizzle
over north central for the next couple of hours) given the classic
drizzle sounding, with a saturated layer from the surface to about
900mb/lift and dry air right above it. Latest obs back this up with
ceilings only 500-600ft. As these lower clouds move out (and
ceilings improve)this will end the drizzle threat, however, with
the clouds hanging over NESD/MN this could continue the drizzle
threat well through the afternoon, as soundings suggest. So I
did add drizzle mention into the grids until 15Z for now. Less
confidence beyond this time but may need to be extending over
our eastern CWA.

As winds become light tonight, mainly out of the south, with the
saturated grounds combining with radiational cooling, the potential
for fog/drizzle is looking possible and potentially could be
widespread. NAM soundings across the entire CWA show some lift in
the saturated lower levels at ~900mb and below. REFS backs this
up, leading to higher confidence, as it indicates widespread
low clouds, in the form of fog, forming over central SD
overnight and potentially spreading across NESD/MN through
Wednesday morning. It could be dense as REFS/HREF probability of
visibility (by 12Z Wednesday) at 1/4th mile or less is up to
50-80% with these higher values between the Mo and James River.
However NBM says 15% or less. Latest run of the ConsShort does
in fact show viz tanking lowest over this location. The only
thing that could hamper this is if lower clouds move back in
quicker with this next system or there is less low level
saturation aka dewpoint depression is higher. So a Fog Headline
may be needed, especially for areas between the Mo and James
River, as the next shift can look at this.

Through Wednesday aloft, the region will be in west to southwest
flow as a large closed mid level low will track southeastward and
over western Canada. With this, a couple of shortwaves will spin
cyclonically around the low with the first one clipping northwestern
SD/western ND/MT this afternoon and the other one tracking
northeastward across the Dakotas tonight through Wednesday
afternoon. The first wave and its surface low will keep any precip
chances to the northwest and north of the CWA. With the Wednesday
wave and its low/cold front, precipitation chances return. The
highest pops of 60-85% will be ahead of the cold front James
Valley and eastward with the highest pops of 70%+ Coteau and
eastward with south to southwest flow ushering in moisture
combining with daytime heating and lift from the front. Models
suggest even some marginal CAPE for thunderstorms! By the
evening, the entire CWA will be behind the front with dry
weather forecast Thursday through Friday as a high will be
dominant over the area. Any shift in the low`s track or timing
will result in a change to pops. Luckily Ptype will be all rain
a highs will be in the 50s to the lower 60s. Precip chances look
to return Friday night through the weekend. Aloft will consist
of a -PNA setup as a ridge will build over the region
Friday/Saturday before tracking eastward as the trough over the
western CONUS tracks east.

Highs for today will range in the mid 40s to the lower 60s, warmest
over south central SD with overnight lows in the 30s to around 40.
However, confidence remains lower on how warm we will get today as
the NBM 25-75th spread is 4-7 degrees due to the clouds and how fast
they can clear out by peak heating. Same for Wednesday with the
clouds, with a spread of 5-8 degrees. Through the end of the
week, temps will remain normal to slightly above normal with
with overall highs in the 50s to lower 60s, but the spread does
increase as well.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1229 AM CDT Tue Oct 27 2026

Terminals KABR,KATY,KPIR,KMBG

LIFR/IFR conditions are expected to prevail at all terminals
through the majority of this morning. Light drizzle and fog will
be persistent through this time frame, however KATY will
continue to hold onto a light rain mention for the first few
hours of this TAF cycle. Conditions will gradually improve at
KPIR/KMBG closer to midday into the afternoon as southeast wind
gusts between 20-25 kts kick in. Low cigs will remain stubborn
however until late is this forecast cycle.

&&

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

&&

$$

DISCUSSION...MMM
AVIATION...Vipond