Swan Lake, South Dakota Weather Forecast Discussion

418
FXUS63 KFSD 151149
AFDFSD
Area Forecast Discussion
National Weather Service Sioux Falls SD
649 AM CDT Mon Sep 15 2025
.KEY MESSAGES...
- Temperatures remain above normal through tomorrow before a cooldown
  back to near to slightly below normal temperatures is
  expected for the second half of the week.
- Isolated strong to severe storms are possible tomorrow
  afternoon and evening, along with a heavy rain potential
  tomorrow night. Plenty of uncertainty remains, so keep up to
  date with the latest forecast.
- A multi-day rain risk develops into the upcoming weekend, with
  heavy rain possible again Wednesday and Thursday. There`s
  around a 40-70% chance of at least a half of rain on
  Wednesday, and a 20-50% chance of that on Thursday.
&&
.DISCUSSION...
Issued at 353 AM CDT Mon Sep 15 2025
Scattered showers and storms from earlier have dissipated as
the upper-low continues lifting north and the LLJ continues on
the downward trend. Lingering stratus around daybreak mainly
along Highway-14 could spit out a few sprinkles with RAP
soundings showing a little bit of elevated instability around 10
kft. However, any rain that falls will encounter some dry air
on its way down and thus most, if not all of us should be dry
during the morning commute. Clouds will clear out through the
morning hours, leading to mostly sunny skies across the area. It
will be breezy with southerly winds around 10-15 mph with gusts
up to 25-30 mph, strongest west of I-29. Highs today with the
southerly flow and sunshine will climb above normal once again
with temperatures in the low-to-mid-80s this afternoon. Some PVA
around 700 mb late this afternoon into the early evening could
trigger a rogue storm in northwest Iowa where the cap is
weakest, but the better chances will be east of the CWA. If a
storm does happen to develop, there will be around 1500-2500
J/kg of MLCAPE to work with, but less than 15 kts of bulk shear
and the chance for severe weather is low, though an isolated 60
mph wind gust cannot be entirely ruled out. But again, chances
for even storm development are quite low (

NWS FSD Office Area Forecast Discussion