Sisseton, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

872
FXUS63 KABR 281050
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
550 AM CDT Sat Jun 28 2025

.KEY MESSAGES...

- Showers/storms (30-60% coverage) early this morning with a low
risk of severe weather.

- SLIGHT RISK (2 of 5) again for this afternoon, east of a line from
Pierre to Aberdeen. Wind and hail are the primary threats,
though can`t rule out a brief tornado in far eastern SD/western MN.

- Another cluster of storms (40-60% coverage) coming up from the
southwest early Sunday morning for central South Dakota before
spreading east through the morning. Low risk of severe weather.

&&

.UPDATE...
Issued at 541 AM CDT Sat Jun 28 2025

Many updates this morning as we have developed widespread light
showers and weak thunderstorms with the wave that is now situated
overhead. The surface low/boundary is also located just to the
northwest of Philip. This placement is a little farther west in
comparison to earlier forecasts and may impact the forecast
location for storms this afternoon. Thats something that may need
redress once the 12Z CAMS become available.

See below for the update to the aviation discussion.

&&

.DISCUSSION...
Issued at 154 AM CDT Sat Jun 28 2025

Cluster of storms in North Dakota threatens the northern CWA if any
of the stronger storms decides to deviate to the right on a 320-340
degree trajectory. Otherwise we just have some weak convection
smattered across the CWA mainly east river. All this is covered by
current POPs. There is the question of whether this will get more
organized overnight and lay down enough outflow to influence the
final location for a surface trough ahead of a low across eastern
South Dakota as a location for re-development later today. The
responsible shortwave is taking its time moving east, so CAMS have
highlighted this area for another round of potential severe weather.
Additionally, another wave, back into  Wyoming will make it into
western South Dakota this evening.  Strongest activity would be out
towards the hills region, however as the wave continues east
northeast elevated convection could be coming into the Missouri
valley towards the morning hours Sunday.

So, for this afternoon, profiles indicate decent mid-level flow of
40kts, though jet level winds are pretty weak with the 200mb jet
over North Dakota. 1/2km winds are about 25kts down in the southeast
CWA before they decouple as a low level jet forms southeast of the
CWA. CAPE is once again up to between 3500-4000j/kg but with only
30kts 0-6 km shear. Thats enough shear for supercell
characteristics, but with westerly mid-levels outflows will also
impact storm mode. And the frontal boundary shifts storms out of the
CWA before the low level jet influences storm mode.

There is the shortwave out west that CAMS have latched onto. Better
shear environment remains to the north, with steeper mid-level lapse
rates up that way, while down into central South Dakota its a weaker
shear/weaker MUCAPE environment. Will probably just end up with
early morning pulse convection in central SD.

An upper level trough sets overhead for Sunday, with weak high
pressure. We get clipped by a backdoor front Monday with a brief
cool down. A broad weak ridge builds in from the west for the middle
of next week, with a series of weak ridge riders keeping POPs in the
forecast mainly for the latter half of next week. No major thermal
anomalies though 700mb temperatures are creeping up towards +14 by
Thursday/Friday.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 541 AM CDT Sat Jun 28 2025

Terminals KABR,KATY,KPIR,KMBG

Mainly VFR conditions, though we have some IFR CIGS lingering
around KATY. Clusters of VFR VISBY/CIG showers early this
morning will also impact terminals. Later today, we have the
greatest potential for afternoon strong thunderstorm activity at
KATY and possibly KPIR/KABR. Additionally, late in the TAF period
we could have a second cluster of storms come out from the west
and impact KPIR and possibly KMBG.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&

$$

UPDATE...07
DISCUSSION...07
AVIATION...07