042
FXUS63 KFSD 282332
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
632 PM CDT Wed Oct 28 2026

.KEY MESSAGES...

- Severe weather risk has come to an end this evening. Rain
  chances end from west to east through the late evening hours.

- Clearing skies with decreasing winds will lead to some fog
  development into early Thursday, especially near and west of
  Interstate 29. Visibility may fall below a mile (20-50%
  chance). Fog dissipates by mid morning.

- Rain chances with some isolated thunderstorms return early
  Friday morning and continue through Saturday and again early
  next week.

&&

.UPDATE...
Issued at 631 PM CDT Wed Oct 28 2026

Severe weather risk has come to an end as the initial cold front and
area of convergence has moved to the east of the forecast area.
Stratus is clearing behind the secondary front/CAA and as surface
high pressure moves into western SD. Expect some showers/drizzle as
the stratus tracks east and clears through the late evening hours
and early overnight. Fog is expected to develop as winds become
light, with some low to moderate (20-50%) chances of visibility
below one mile into Thursday morning. Greatest risks for fog remain
near and west of I-29, with most guidance highlighting the James
River Valley in particular. Lows tonight may fall into the lower 30s
west of the James, with 30s to lower 40s elsewhere. Fog lifts by mid
morning, with a pleasant day on tap for Thursday in the mid 50s to
mid 60s.

No adjustments to the forecast outside of this evening/tonight. Rain
chances return with some isolated thunderstorms possible Friday into
Saturday.

&&

.DISCUSSION...
Issued at 131 PM CDT Wed Oct 28 2026

Over the next couple of hours, showers and storms are expected
to develop over parts of eastern South Dakota and western
Minnesota ahead of a cold front. Cannot entirely rule out the
possibility of strong to severe thunderstorms, although the best
environment will be to the northeast further into Minnesota.
Still, a Marginal Risk clips the northeastern-most part of the
forecast area, and hail is the main potential severe threat.
Strong storms that do develop in that area are expected to exit
the forecast area fairly quickly this afternoon. Further south,
expectations are that showers will remain fairly light, and just
a few hundredths of rain will fall.

Behind the cold frontal passage, a high pressure center will move
into the area overnight tonight. After an initial shift to the
northwest, winds will become light and variable overnight tonight as
the high pressure center moves overhead. There is some signal in
high-resolution guidance for some fog development once again tonight
due to the light winds and clear skies promoting strong radiative
cooling. The main area of concern for fog development is over
southeastern South Dakota, particularly the James River Valley.
Confidence in the areal coverage is still somewhat low at the
moment, but pockets of dense fog may reduce visibility below a mile
at times.

The next chances for rain come on Friday into Saturday. Rainfall
will move in from the south beginning Friday before expanding to
cover the entire forecast area Friday night into Saturday. Generally
light rain rates are expected, but perhaps a quarter of an inch or
more (20-40%) could fall over parts of northwestern Iowa,
northeastern Nebraska, and southwestern South Dakota.

Another low pressure system is set to move into the region early
next week, bringing renewed chances for rain into the region. Monday
through early Wednesday, chances are fairly high (50-70%, increasing
moving from north to south across the forecast area) to see an inch
of rainfall accumulation or more. However, there is still
significant uncertainty with this system in timing, location, and
amounts. 25th/75th spread is generally around two inches for that
same time period, so still a lot to resolve as the system comes into
focus over the next couple of days.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 631 PM CDT Wed Oct 28 2026

MVFR/IFR stratus (isolated LIFR) and rain showers/drizzle continue
to move east through the late evening and early overnight hours.
Behind this, clear skies prevail. With clearing skies and decreasing
winds overnight, MVFR to IFR fog is expected to develop into
Thursday morning. Greatest risk is near and west of I-29, and
especially in the James River Valley. May see visibility drop below
1SM (20-50% chances). May also see some ceilings below 1kft if the
fog is a thicker layer or stratus develops.

Conditions improve by mid Thursday morning, with VFR conditions
through the rest of the period. Southeasterly winds prevail around
10 knots or so, with gusts around 20 knots during the afternoon in
south central SD.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.

&&

$$

UPDATE...SG
DISCUSSION...
AVIATION...SG