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000
FXUS63 KFSD 172248
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
548 PM CDT Wed Apr 17 2024

.KEY MESSAGES...

- More light to moderate rain showers will return overnight
  mostly south of I-90. Additional accumulations will vary
  between 0.25"-0.75" of an inch with the highest accumulations
  expected between the I-90 and Hwy-20 corridors.

- Our overall temperatures will continue to gradually decrease
  into the weekend with overnight temperatures dropping below
  freezing. Any sensitive spring-time plants will likely need to
  covered if possible.

- More concrete rain chances (30%-60%) could potentially return
  by Monday. However, details remain uncertain at this time.

&&

.DISCUSSION...
Issued at 348 PM CDT Wed Apr 17 2024

A breezy day continues! Taking a look across the area, quieter and
clearer conditions have temporarily returned this afternoon as a mid-
level ridge moves into the region from the west. Breezy
northwesterly surface winds will continue to gradually decrease this
afternoon as the ridge moves overhead. Nonetheless, with
northwesterly surface flow in place and lingering cold air advection
(CAA) aloft, our overall temperatures will be a lot cooler than the
previous days with highs only expected to peak in the upper 50s to
low 60s. Look aloft, our attention will likely shift to our southern
border as a quick shortwave moves through our area. As increasing
700 mb frontogenesis interacts with some isentropic lift ahead of
the cold front, areas of light to moderate showers will develop
across southcentral SD and spread eastwards late this evening with
accumulations ranging from a few hundredths along the Hwy-14 corridor
to between 0.25" to 0.75" of an inch between the I-90 and Hwy-20
corridors.

Expect most of the developing showers to continue into the
overnight hours with most of the activity dissipating by daybreak
Thursday morning. Lastly, the increased cloud cover will keep
temperatures a bit elevated overnight with low only decreasing into
the upper 30s to low 40s for the night. Looking into Thursday,
cooler and clearer conditions return as a surface ridge moves in
from the northwest. Similar to today, an increasing SPG will lead to
breezy northwesterly winds with gusts between 25-35 mph expected.
Otherwise, a deeply mixed environment along with lingering CAA aloft
will lead to colder air getting transported to the surface. As
a result, our overall temperatures will continue to decrease
with highs expected to only get into the low to mid 50s for the
day. This trend will carry over into our overnight temperatures
as well with lows dropping below freezing for the first time in
a few weeks. With this in mind, if you have any sensitive
spring-time plants that are susceptible to chilly temperatures;
you might want to consider covering them.

Looking into the weekend, broad upper-level troughing north of the
international border will continue to affect the northern plains as
multiple waves rotate around the system. While our precipitation
chances will be limited, continuous infusions of CAA aloft and
deep mixing will help continue the cooling trend over the
weekend. As a result, highs likely sit in the upper 40s to low
50s through Saturday. Temperature will likely be even cooler
overnight with lows expected to drop into the mid to upper 20s
and low 30s through Sunday morning. However, a pattern shift
will likely be on the horizon by Saturday night as upper level
ridging brings a shot of warm air advection (WAA) to the region.
This along with a shift towards more southerly to southwesterly
surface flow will help temperatures gradually warm back into
the mid to upper 50s and low 60s to start the week. Lastly, more
concrete rain chances (30%-60%) could potentially move through
the region on Monday as a clipper wave slides southeastwards.
However, the details remain uncertain at this time.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 546 PM CDT Wed Apr 17 2024

Rain showers will overspread the area after 04Z, with lowering
visibility and ceilings (MVFR) at KFSD and KSUX. Showers will
move eastward by late tonight into Thursday morning, with
improving visibility and ceilings. Northwesterly winds will
increase on Thursday morning, gusting around 25kts through the
afternoon.

&&

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

&&

$$

DISCUSSION...Gumbs
AVIATION...JM