985
FXUS63 KFSD 140346
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
1046 PM CDT Fri Jun 13 2025

.KEY MESSAGES...

- Areas of fog are again expected along the Buffalo Ridge and
  east central SD tonight into early Saturday resulting in
  reduced visibility.

- An active pattern looks to bring continued chances for showers
  and storms for the weekend and at least early next week. While
  finer details remain uncertain, continue to monitor the
  forecast for strong to severe storms and heavy rain potential.

&&

.DISCUSSION...
Issued at 218 PM CDT Fri Jun 13 2025

Rest of Today: Boundary currently draped from roughly north of
Windom to just north of Sioux City, near this boundary (mainly in SW
Minnesota) a few showers or weaker thunderstorms are possible into
the evening hours. While unlikely, NST parameter of 1-3 and low level
CAPE/surface vorticity overlap leave at least some remote chance for
any developing shower/storm to develop a funnel cloud or landspout.

Tonight: Could again see some fog leak down the Buffalo Ridge of SW
Minnesota and perhaps the higher elevations of Jerauld and Beadle
county. Also not impossible for some showers or weaker thunderstorms
to develop along the next WAA push although chances of measurable
precipitation at any one location currently look low (<20%).

Saturday: Weak wave moves from west to east through northern South
Dakota and thus will carry some shower and thunderstorm chances (30-
50%) north of I-90 during the daytime hours with lesser chances
south of there. Synoptic boundary looks to get hung up somewhere
near Hwy 14 with next wave sinking into southeast South Dakota. This
would likely bring a bit better chance (50-70%) of thunderstorms by
the evening and overnight hours with probably still the overall
better focus being north of I-90. This would also likely be the
period to watch for an isolated stronger storm with a current
Marginal risk from SPC. Baring any convective contamination, high
temperatures in the 80s look likely for most locations with lower 90s
toward the MO River Valley.

Sunday through Wednesday: An unsettled pattern continues through the
first half the week but also one that carries daily uncertainty with
many of the drivers for convection chances dependent on what occurs
in the previous day(s). While the finer details of where and when
are still murky, pattern recognition, initial SPC outlooks and
machine learning probabilities/analogs suggest this period will
carry daily regional severe weather risks. At this time, would
suspect that the better chances for any more widespread severe
thunderstorms would be Monday night into Tuesday and then again
Tuesday night and early Wednesday as better waves lift through the
area within the broader southwest flow. With potential for multiple
rounds of convection and PWATs climbing near or above the 90th
percentile of climatology, will also want to monitor for potential
flash flood/flood related issues during this timeframe. This is
confirmed by some signal in 5 Day National Water Model guidance.

Wednesday through Friday: Main trough finally lifts through the
local area sometime Wednesday with building ridging by the end of
the work week. Cooler conditions with temperatures back into the 70s
behind the system Wednesday, quickly recovering to the 80s or even
lower 90s by next weekend.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1045 PM CDT Fri Jun 13 2025

MVFR/IFR stratus continues to sink southward this evening, and
may overspread areas along and north of the Interstate 90
corridor through early Saturday afternoon. In addition, patchy
fog will be possible late tonight into Saturday morning, focused
along the Buffalo Ridge into east central SD.

Shower/thunderstorm chances are low (20%) overnight, though
chances will increase on Saturday afternoon and evening.

&&

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

&&

$$

DISCUSSION...Kalin
AVIATION...JM