377
FXUS63 KFSD 171109
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
609 AM CDT Fri Oct 17 2025

.KEY MESSAGES...

- More typical Fall weather expected through the upcoming
  weekend, with increased risks for Saturday rain and wind.
  Temperatures remain near normal both days.

- Saturday`s rain chances have increased, but overall
  precipitation amounts will remain less than 0.25". Stronger
  wind gusts over 30 mph may arrive in the afternoon.

- Quiet weather is expected for most of next week, though
  several fronts pass through the region. A front on Monday
  brings potential for 40+ mph winds and sprinkles/showers into
  Tuesday.

- Lighter winds and near normal temperatures either side of 60
  degrees expected through the remainder of the week.

&&

.DISCUSSION...
Issued at 214 AM CDT Fri Oct 17 2025

THIS MORNING:   Light rain will continue to slowly drift east, while
continuing to diminish through daybreak.  Precipitation amounts less
than 0.10" are expected.  Some stratus is already developing behind
a weak front that bisects the CWA this morning.

TODAY: The aforementioned front remains draped from SW to NE through
the CWA at daybreak, likely leading to the development of a narrow
band of lower stratus and perhaps lingering drizzle into mid-
morning.   However the shearing out mid-lvl vorticity along with the
arrival of a stronger push of 925:850mb dry air should diminish
these clouds/precip quickly through the morning. Westerly winds
then prevail through the day with temperatures climbing into the
upper 60s to lower 70s.

TONIGHT: A secondary mid-lvl front drops southeast overnight,
bringing a return of mid-upper clouds overnight.  Low temperature
remain a bit uncertain, with increased cloud cover suggesting
temperature remain above deterministic NBM guidance. However if
winds turn variable and clouds are thin, then temperatures in the
middle 30s are possible.

SATURDAY: A stronger mid-lvl trough drops into the Northern Plains
on Saturday, bringing an increasing risk for mid-day and
afternoon light rain to the region. Not much in the way of
instability with the passage of this trough, so will keep any
thunder mention out of the forecast. Rainfall amounts won`t be
all that high, with LPMM values only as high as 0.25, with most
less than 0.10". This light rain will fall behind the passage
of a surface cold front, which increases the potential for
falling afternoon temperatures. Models are also picking up on an
increasing wind gust potential with NAM/GFS/EC/ECAMS all
suggesting potential for 30 to 35 mph wind gusts into the
evening. Have boosted winds from populated guidance. Any wetting
mid-day rain and cooling temperatures should limit the fire
danger potential, but it will still be slightly elevated.
Clearing skies and light winds may lead to frost Sunday morning.


SUNDAY-TUESDAY:  Surface ridge axis sliding east along with low-lvl
warm advection should lead to a very nice Sunday in the region.
However another strong trough is expected to drop into the
Northern Plains by the start of next week. Surface cyclogenesis
developing over the western Dakotas will induce a stronger SPG
through the region into Monday morning with gusty wind through
the night. The passage of the surface low and cold front on
Monday will bring the potential for gusty afternoon and
nighttime winds on Monday. Probabilities of 30+ mph winds from
the NBM and LREF guidance are over 60%+ in many areas, with raw
deterministic guidance from the EC/GFS/CMC all showing 40-45 mph
gust potential. Thus, have boosted winds towards the NBM 90th
percentile into Tuesday, which are still probably too low. At
this point, the passage of this upper trough will be a dry one
in most areas. Perhaps the potential for sprinkles arrives
Tuesday morning as the trough wraps up and moves east. Winds
will weaken quickly Tuesday, however temperatures are likely
going to remain below normal.

WEDNESDAY-FRIDAY: Medium range guidance splits through the
second half of the week, mostly regarding the timing of any
passing trough through the Plains. However, a common theme
remains persistent dry weather conditions into next weekend with
all of the major ensembles showing less than 10% probabilities
of measurable rain.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 607 AM CDT Fri Oct 17 2025

A narrow corridor of IFR to LIFR ceilings have developed this
morning behind a stalled frontal boundary. These clouds will
continue to drift eastwards in the MN/IA counties,

VFR conditions will then return across the area by mid-day as
winds increase slightly from the west.


&&

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

&&

$$

DISCUSSION...Dux
AVIATION...Dux