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000
FXUS63 KFSD 192257
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
557 PM CDT Fri Apr 19 2024

.KEY MESSAGES...

- A few light sprinkles to light showers will be possible
  through early evening mostly along the Hwy-14 corridor and
  portions of southwestern MN. Light accumulations are expected.

- Below freezing temperatures overnight will continue through
  Sunday morning potentially creating some frost/freeze concerns
  across portions of the area.

- More light rain chances (20%-50%) will return by Monday.
  However, only light accumulations are expected.

&&

.DISCUSSION...
Issued at 233 PM CDT Fri Apr 19 2024

Short Term (Rest of the Afternoon/Tonight & Saturday):

Another breezy day continues! Taking a look at satellite imagery, a
robust cumulus field with some embedded sprinkles to flurries has
developed from the I-90 corridor northwards as a broad upper-level
low (ULL) continues to traverse the Northern Plains and Great Lakes
Regions. Increasing isentropic lift along with a 50-60 kt LLJ could
help slightly increase the coverage of this developing light
precipitation into this evening. However, with around a 20 degree
dew point depression present for most areas mostly due to dry air;
accumulations are expected to be kept to a minimum. Shifting gears
to our winds, many of our observation sites continue to report
sustained northwesterly winds between 20-30 mph with gusts between
35-45 mph with a few isolated gusts up to 50 mph. Since this falls
within advisory criteria, a Wind Advisory has been issued for areas
roughly along and northeast of a Beadle county to Minnehaha county
to Buena Vista county line through 23z with the possibility of
expansion if needed.

Lastly, with conditions largely expected to clear later tonight;
temperatures will likely to plummet fairly quickly after sunset with
overnight lows expected to be in the mid to upper 20s. With this in
mind, a Freeze Warning will be in effect from 05z to 12z for most
areas along and east of I-29. However, with winds expected to stay
slightly elevated overnight for most of the area; frost development
could be a bit more patchy than the previous day. By Saturday, the
cool and quiet conditions will continue as a surface highs slides
across the western portions of the Dakotas and central portions of
Nebraska. Similar to today, another fairly mixed day will lead to
marginally breezy northwesterly winds with gusts between 15-25 mph.
Looking aloft, weak warm air advection (WAA) ahead of a quick
shortwave will help our highs recover to upper 40s to low 50s for
the day. Otherwise, another cool and quiet night will be on tap as
low drop into the mid to upper 20s. With this in mind, another
frost/freeze headline will likely be needed especially since
winds are expected to drop off after sunset.

Long Term (Sunday-Thursday):

Heading into the extended period, slightly warmer conditions will
return by Sunday as an upper-level ridge moves in from the west
along with southerly to southwesterly surface winds. The combination
of increase WAA and southerly to southwesterly surface flow will
lead to warmer temperatures in the upper 50s to 60s with the
potential for some low 70s along the Missouri River by Monday.
Looking aloft, our next rain chances (30%-50%) will likely come on
Monday as an upper-level waves dives southeastwards across the
plains. However, with the low shifting further northwards with this
round of guidance; accumulations will be limited and mostly isolated
to areas east of I-29 with most ensemble guidance showing low
confidence (10%-30%) in QPF equaling a tenth of an inch. Otherwise,
the SPG will tighten ahead of this system leading to breezy
southerly to southwesterly winds with gusts between 30-40 mph
expected.

From Tuesday through Thursday, much quieter conditions return as
another upper-level ridge moves in from the west. Increasing WAA in
the mid-levels along with the return of southeasterly surface winds
will lead to highs in the upper 50s to low 60s on Monday and
highs in the low to mid 60s by Wednesday and Thursday. Lastly,
some long-range guidance has started to show some potential
rain chances developing from Thursday into Friday as a shortwave
ejects out of the Rockies. However, timing and location differences
among guidance have lead to a bit of uncertainty at this time.
Either way, this will be a system to monitor moving forward.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 553 PM CDT Fri Apr 19 2024

VFR conditions are expected through the TAF period. Gusty
northwesterly winds will taper downward during the evening.
By Saturday morning winds will increase again, gusting around
20 kts through the afternoon.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...Freeze Warning from midnight tonight to 7 AM CDT Saturday for
     SDZ055-056-061-062-066-067-069>071.
MN...Freeze Warning from midnight tonight to 7 AM CDT Saturday for
     MNZ071-072-080-081-089-090-097-098.
IA...Freeze Warning from midnight tonight to 7 AM CDT Saturday for
     IAZ001>003-012>014-020>022-031-032.
NE...Freeze Warning from midnight tonight to 7 AM CDT Saturday for
     NEZ013-014.

&&

$$

DISCUSSION...Gumbs
AVIATION...JM