Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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FXUS63 KFSD 262040
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
340 PM CDT Tue Mar 26 2024

.KEY MESSAGES...

- Breezy northwesterly winds will continue decreasing into the
  evening hours, bringing an end to the drifting of snow on the
  roadways.

- Quiet conditions prevail Wednesday, though afternoon highs
  will be 15 to 25 degrees below normal in the lower 20s to mid
  30s.

- Temperatures warm Thursday and Friday, with temperatures
  forecast to get back to seasonal normals on Friday.

- Precipitation chances return on Friday and again on Sunday,
  though confidence in track and amounts remaining low at this
  time.

&&

.DISCUSSION...
Issued at 339 PM CDT Tue Mar 26 2024

Early afternoon satellite imagery shows some remaining stratus from
our previous system dissipating and/or sliding eastwards, with
surface observations showing temperatures in the 20s with breezy
northwesterly winds gusting into the 30s. Have been seeing some
scattered convective snow showers develop resulting in modest
visibility reductions, though as instability wanes later this
afternoon those showers will dissipate. As a lobe of vorticity from
the main upper level wave slides overhead, our previous surface low
pressure system will be pulled northwards, which will relax the
surface pressure gradient (SPG) across the area resulting in
decreasing wind speeds. Overnight, a surface high pressure will be
sliding down from southern Canada, with cold air advection (CAA)
bringing chilly temperatures along with it. We`ll likely start
Wednesday with temperatures in the positive single digits across the
region, aside for areas across NW IA which will be in the teens due
to their lack of snowpack.

Quiet conditions continue throughout the day as the surface high
continues to slide overhead, with the cold temperatures also
continuing. Max temperatures by the afternoon hours look to remain
in the lower 20s to lower 30s for areas with the new snowpack, and
up into the upper 30s for areas with no snow on the ground. While
these temperatures are 15-25 degrees below normal, not expecting any
record cold max temperatures to be broken as those temperatures are
an additional 5+ degrees colder. We`ll see these cold temperatures
continue overnight into Thursday, where low temperatures will likely
again dip down into the single digits to lower teens along and north
of I-90, and teens to lower 20s south of I-90.

Throughout the day, we`ll see an upper level ridge move towards the
region from the west, with shortwaves moving across the Rockies
behind the ridge expected to develop another surface low pressure
well off to our west. However, the associated warm front will be
extending into the central plains, and will help to aid the
beginning of our warm-up, though the front looks to remain south of
the area on Thursday. With the weak ridging that moves overhead,
temperatures look to warm up into the 40s and lower 50s for areas
that are able to melt their snowpack, while areas that still have a
snowpack at that time may struggle to get out of the 30s.

Overnight into Friday, the surface low moves into the central
plains, and brings our next chance for precipitation, though current
deterministic and ensemble guidance would suggest best chances
occurring north and east of our area. Ensemble clustering analysis
remains fairly evenly split (35/24/22/19), with the most favored
cluster looking very similar to the others in regards to
precipitation chances. Given the close proximity to the warm front
and shallow cold air north of the front, it`s a decent set-up for
freezing rain north of I-90, but with ensembles/clusters suggesting
precipitation chances remaining low (<30%) doesn`t look to cause any
concern. As for temperatures, this will depend largely on how much
work has been done on depleting the snowpack, but for areas that
have no snow could see temperatures into the 50s and lower 60s.

For the weekend, the ridge over the CONUS looks to expand northwards
as a strong upper level low moves down the west coast. Solutions
continue to vary as to when and where the surface low pressure
develops (Sat/Sun/Mon?), and with our area having a surface high
pressure influencing the region from the north, we`ll have to see
how those two will interact.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1230 PM CDT Tue Mar 26 2024

Seeing some scattered snow showers develop early this afternoon,
likely continuing throughout the rest of the afternoon, with the
main impact being brief MVFR visbys. Breezy northwesterly winds
will be decreasing throughout the afternoon hours, with
MVFR/IFR cigs lifting and/or sliding eastwards into the evening
hours. VFR conditions return overnight and throughout the day on
Wednesday.

&&

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

&&

$$

DISCUSSION...APT
AVIATION...APT


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