129
FXUS63 KFSD 121754
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
1154 AM CST Wed Nov 12 2025

.KEY MESSAGES...

- Patchy valley fog will be possible tonight and Friday morning.

- Mild temperatures will continue for most of the workweek with
  the warmest conditions expected by Friday. Temperatures
  moderate near seasonal early next week.

- Drier conditions will persist into the weekend with our next
  rain chances (20%-30%) potentially returning early next week.

&&

.DISCUSSION...
Issued at 251 AM CST Wed Nov 12 2025

THROUGH TONIGHT: Cirrus clouds continue to stream southeast this
morning across central SD and across eastern SD into northwestern
IA. Temperatures through 3 AM are in the 30s, and we should drop a
few more degrees before daybreak. Will be watching for fog
development in river valleys through the mid morning hours. HREF
probability of visibility below 1 mile is 40% or less. Be prepared
for some patchy fog during the morning commute.

A little breezy this afternoon, mainly along the higher elevations
of the Buffalo Ridge where we mix into the stronger LLJ. Not quite
as warm today with northwesterly flow and cooler temperatures aloft;
however, warmed highs by a few degrees across the area given how
dramatically we exceeded forecast highs yesterday even with snow
pack. Highs today in the 50s. Expect a mix of clouds and sun through
the day, with clouds increasing tonight. Lows fall into 30s. Can`t
rule out some patchy valley fog tonight as well.

THURSDAY-FRIDAY: Ridging moves east through the end of the week,
with the ridge axis overhead Friday. A couple weak perturbations
track through the synoptic flow, but conditions remain dry with a
lack of moisture. Prevailing southerly low level flow and WAA with
the building ridge allows for well above average temperatures. Highs
by Friday warm into the 60s and even 70s with overnight lows in the
upper 30s to mid 40s (averages are the mid 40s for highs and mid 20s
for lows).

May see some valley fog Thursday and Friday mornings if winds remain
on the lighter side. Breezy Friday with the compressed surface
pressure gradient and more efficient mixing. This may lead to some
areas of elevated fire danger especially for south central SD given
we`ll have had a few days to dry out and our well above average
temperatures.

FRIDAY NIGHT-TUESDAY: More active pattern returns for the weekend
and into early next week, although guidance continues to vary on
timing/track of troughs/low pressures. Surface cold front and wave
aloft move through late Friday night into Saturday, with the 12.00z
ECMWF the quickest in moving this through. Probability of measurable
precipitation during this time is low (less than 20%) and confined
to north of I-90 toward US Hwy 14. Saturday may also see elevated
fire danger due to breezy winds, although RH values remain above
critical.

Short lived ridge builds in for Saturday night through Sunday with
troughing sweeping through the Midwest. 12.00z guidance has
continued to trend slower with the wave early next week, with the
GFS/ECMWF leaning toward an open wave with the Canadian bringing a
closed low into the Plains Monday evening. This continues to be our
next best chance of precipitation, with NBM pops now in the 20-40%
range late Sunday night into Monday. At this time, measurable
precipitation is likely (probability over 60%), with moderate (40-
60%) chances of more than a tenth of an inch. Temperatures may be
cold enough for some light accumulation of snow, although confidence
in p-type is low at this time given the differences in model track.
Temperatures through early next week moderate back to near seasonal
normals.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1150 AM CST Wed Nov 12 2025

VFR conditions will persist this TAF period. Besides a few
higher clouds this afternoon and evening, most clear and quiet
conditions will persist. Otherwise, light southeasterly winds
will become more light and variable this afternon with the
approaching surface high to end the TAF period.

&&

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

&&

$$

DISCUSSION...SG
AVIATION...05