Brandon, South Dakota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

897
FXUS63 KFSD 180437
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
1037 PM CST Fri Jan 17 2025

.KEY MESSAGES...

- An arctic air mass settles into the northern Plains tonight,
  bringing an extended period of very cold weather. Confidence
  is high (>80%) that we will see well below normal temperatures
  from Saturday through Tuesday, with multiple nights of wind
  chills colder than -20F.

- Temperatures moderate for the middle of next week, with no
  significant winter systems on the horizon.

&&

.DISCUSSION...
Issued at 231 PM CST Fri Jan 17 2025

The surface cold front continues its trek southeastward this
afternoon, and is expected to be fully through our region by early
this evening. Behind the front, strong northwesterly winds are
gusting 35-45 mph. Occasional gusts to 50 mph are also
possible. Therefore, a Wind Advisory has been issued for this
afternoon until 6pm CST, for portions of central and east
central South Dakota. Winds will slowly diminish through the
overnight, but will remain breezy with gusts 20-25 mph through
Sunday morning. In addition to the gusty winds, low chances
(<25%) of light snow are possible through this evening. Any snow
showers that develop will have to contend with some dry
subcloud air, and so any accumulation should be light. However,
with the strong winds, even light snow can reduce visibility.
So, please use caution as you make your way this afternoon and
evening.

Temperatures behind the front are rapidly falling from the 30s to
the 20s and teens. Temperatures will continue to fall through
Saturday morning as bitterly cold arctic air continues to flow in
from the northwest. Lows for just after sunrise Saturday will be in
the single digits above zero. Afternoon temperatures rebound
slightly to around 7-17 degrees. Wind chills Saturday morning will
be cold, in the -10 to -20 range, with the coldest temperatures
across southwestern Minnesota. Cold weather will be the main story
through Tuesday of next week. Cold lows in the -5 to -10 range,
coupled with the slightly breezy winds will result in wind chill
values falling solidly into advisory criteria. As such, we have
issued a Cold Weather Advisory for the entire region from 9pm
Saturday night, until noon Sunday. Wind chills will range from -25
to -30 with areas of higher elevation along the Buffalo Ridge in
southwestern Minnesota falling as low as -35 briefly. We will
continue to monitor trends, as additional headlines may be needed.

As mentioned, breezy conditions continue through Sunday afternoon,
with gusts 20-25 mph. A secondary push of CAA Sunday morning, the
result of an embedded shortwave, will further cool our high
temperatures into the low single digits. Again the coldest
temperatures will be at elevation along the Buffalo Ridge, where
highs may struggle to break zero. Though wind chills are expected to
recover in the afternoon, they will still be cold in the negative
teens. Lows for Sunday night/Monday morning will be in the -5 to -15
range, which will result in another night of bitterly cold wind
chills. Wind chills shortly after sunrise on Monday will be in the -
20 to -30 range. While this does put portions of our region into
Cold Advisory criteria again, after collaboration with neighbors, we
have opted to hold on issuing further cold weather headlines at this
time. However, if the trends hold, headlines will likely be needed
for Monday morning and possibly Tuesday morning.

Monday highs will be in the low single digits above zero for areas
south of I-90. To the north, most areas will struggle to warm above
zero. Breezy conditions with gusts again in the 20-25 mph range will
keep wind chills in the negative teens to negative 20s for the
entire day Monday. Monday night winds finally go light, however with
lows in the -10 to -15 range, wind chills will still be a factor.
Most areas will see wind chills bottom out in the -20 to -30 range
just before sunrise Tuesday. Thankfully this will be the last
bitterly cold morning as temperatures begin to rebound as a weak
upper ridge turns surface winds southerly, and usher in warmer air.
Highs for Tuesday will range from around 10 to 20 degrees above
zero. Another fast moving Clipper system moves through the region
Wednesday, bringing the next chance for some light precipitation. At
this time confidence in details remains low.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1031 PM CST Fri Jan 17 2025

Areas of MVFR stratus and flurries into late tonight, before
conditions improve on Saturday morning. Northwesterly winds will
be slowly tapering downward, though gusts around 25 kts will
continue through the majority of the TAF period.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Cold Weather Advisory from 9 PM Saturday to noon CST Sunday
     for SDZ038>040-050-052>071.
MN...Cold Weather Advisory from 9 PM Saturday to noon CST Sunday
     for MNZ071-072-080-081-089-090-097-098.
IA...Cold Weather Advisory from 9 PM Saturday to noon CST Sunday
     for IAZ001>003-012>014-020>022-031-032.
NE...Cold Weather Advisory from 9 PM Saturday to noon CST Sunday
     for NEZ013-014.

&&

$$

DISCUSSION...AJP
AVIATION...JM