Sisseton, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

505
FXUS63 KABR 160525
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
1225 AM CDT Sat May 16 2026

.KEY MESSAGES...

- Dry conditions persist on Saturday with elevated fire weather
  conditions across central SD in the afternoon.

- Storm chances increase Saturday night, continue through Sunday,
  followed by rain Monday.

- Marginal Risk (1 of 5) to Slight Risk (2 of 5) mostly focused
  across central and northeast South Dakota Sunday afternoon.

&&

.UPDATE...
Issued at 1224 AM CDT Sat May 16 2026

Update for 06Z TAF issuance

UPDATE Issued at 750 PM CDT Fri May 15 2026

Southern segment of Red Flag Warning went away at 7 PM CDT.
Remaining segment will be allowed to expire on time in about an
hour from now at 9 PM CDT. Already beginning to see wind speeds
decreasing and relative humidity steadying out/increasing
slightly. The rest of the forecast for tonight remains on track.
No other changes planned at this time.

UPDATE Issued at 618 PM CDT Fri May 15 2026

See below for an aviation forecast discussion for the 00Z TAFs.

&&

.DISCUSSION...
Issued at 252 PM CDT Fri May 15 2026

Mostly sunny skies have dominated the areas today with just a few
streaks of mid level clouds passing overhead. Temperatures have
warms into the 70s to near 80 as dew point temperatures have stayed
fairly steady in the upper 20s to mid 30s. This have led to
afternoon RH percentages from the mid teens to low 20s. Gusty winds
were initially sluggish to get going this morning but have since
picked up to between 25-35 mph this afternoon. So, Red Flag Warning
conditions have been met and that posted headline will remain in
effect into early to mid evening. By sunset, gusty winds will have
diminished across most of the forecast area and RH`s will have
recovered back to around 30-35 percent. Temps overnight look to fall
to near normal with readings in the 40s.

Latest suite of guidance today indicates not much change in the
overall upper flow pattern across the Northern Plains and Upper
Midwest through the weekend into next week. Essentially zonal flow
will persist through Saturday as an upper trough begins to dig into
the western CONUS. This system will make a change in our dry pattern
by the end of the weekend. As it digs farther east, southwest flow
a lot develops across the Northern Plains and it`s anticipated to
send a few successive mid level waves of energy into our Sunday
through Monday. This system is then progged to move out of the
region by the middle of next week which looks to be followed by a
weak and disorganized pattern during the latter half of next week.

Saturday will feature increasing mid level heights associated with
shortwave ridging aloft leaving our area with another dry and warm
day. Forecast sounding still indicate an increase in mid level
moisture with a deep dry subcloud layer, so only anticipate passing
clouds. Sfc high pressure will shift east across ND during the
morning and into northwest MN in the afternoon. This will promote a
east to southeast wind by later in the day into Saturday night. The
pressure gradient does tighten back up across central SD during the
afternoon as lee side cyclogenesis gets underway southwest of our
region. Gusty southeast winds will develop and with RH values
expected to fall to around 20 percent, elevated fire weather
conditons will once again develop. Issued an SPS for now to
highlight this message.

By late evening and early overnight Saturday night, pooling low to
to mid level moisture will be advected northward into our region in
a warm advection process. Expect showers and thunderstorms to
develop late Saturday into early Sunday in our west and southwest
and then track east to northeast through the morning hours with the
first in that series of mid level shortwaves moving through.
Elevated convection for the most part will accompany this with the
potential for a few strong to perhaps severe storms with some risk
for mainly hail. With daytime heating, an unstable air mass
develops, especially across our far southern/eastern zones into the
heart of southeast SD/southwest MN/northwest IA/northeast NE. A
sharp instability gradient looks to develop just off to the
southeast of our forecast area, moreso in southeast SD. Expect more
robust convection to develop there but since we are on the northwest
cusp of this, our southeast zones will have the best chance to see
more active severe storms versus locales farther north and east. A
Marginal to Slight Risk for severe weather has been posted by SPC
for parts of central into northeast SD and west central MN with an
Enhanced Risk just off to our southeast. Large hail will be the
primary threat for our area but localized damaging winds will also
be possible along with locally heavy rainfall. Rainfall amounts will
be highly dependent on the strength and placement of the convection.
Rainfall chances will continue into Monday as another mid level wave
and sfc low tracks southeast of the area. This rainfall looks like
it could linger into Monday night and early Tuesday before finally
tapering off. Drier, cooler conditions set in Tuesday and Wednesday.
In fact, below normal temperatures will be possible by this time
frame. Progs for overnight lows will have to be watched more closely
in the coming days as the potential remains for readings in the low
to mid 30s increasing the potential for frost.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1224 AM CDT Sat May 16 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will continue through the next 24 hours. Non-
diurnal wind are expected Saturday evening, with winds gusting
20-30kts by 03Z Sunday.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Red Flag Warning from 3 PM CDT /2 PM MDT/ this afternoon to 10
    PM CDT /9 PM MDT/ this evening for SDZ033>036-045-048-051.
MN...None.

&&

$$

UPDATE...10
DISCUSSION...Vipond
AVIATION...06