038
FXUS63 KFSD 222321
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
521 PM CST Sat Feb 22 2025

.KEY MESSAGES...

- Well above normal temperatures are expected this weekend into next
  week. The degree of warmth may at least partially depend on
  snow melt/potential for resultant fog development. However
  highs in the 50s will be possible Sunday through Tuesday with
  some 60s in central SD. The 75th percentile of the guidance is
  significantly warmer that the NBM so leaned on that in many
  locations.

- Watch for refreeze of melted snow causing scattered slick spots as
  nighttime temperatures fall back below freezing.

- Predominately dry conditions will persist through next week.
  Low (20%-30%) chances for light rain Monday (mainly north of
  I-90) and again Tuesday night through Wednesday.

- Next week could see some high fire danger as the snow melts
  and temperatures remain mild. Currently the better chance will
  be near and west of the James River.&&

.DISCUSSION...
Issued at 216 PM CST Sat Feb 22 2025

Northwest flow aloft remains in place tonight with an increase as a
jet max pushes east through MT into the Dakotas. This will bring a
weaker wave through just to the north of the area. Model soundings
hint at some moisture aloft with some weak forcing in the dgz.
Fairly dry air is in place below about 800 mb so with the weak
forcing and a general lack of instability, getting precipitation to
the ground looks difficult, at least something more than sprinkles
or very light rain. The better chances for some patchy very light
rain will be in southwest MN. Otherwise light westerly flow will
keep temperatures a bit on the milder side overnight, with lows in
the teens to mid 20s. Will once again see a small threat for patchy
valley fog with a little better snowmelt today and some lighter
winds overnight. The impacts should remain fairly local.

Once this wave passes the low level flow will remain west to
southwest with mainly higher clouds expected. This flow brings in
even milder air aloft and the only challenge may be breaking through
the inversion that develops through Sunday morning. Even without
full mixing temperatures are still on track to be very mild, with
highs from near 60 in central SD to about 45 to 50 near and east of
I-29.

A slightly stronger jet max and mid level wave move into the area on
Monday. Once again moisture and forcing are not overly supportive,
but there may be some minor, weak instability with increased lapse
rates from about 800-400mb. Still not enough to garner more than a
20-40 percent chance or so for a hundredth of an inch of rainfall
with the better chances near and north of highway 14. With this wave
and the expected westerly flow, mild temperatures are again
expected, but may be tempered a bit by the increased cloud cover
from this wave. Highs mostly from 50 to 60 degrees, warmest in
central SD. A really good potential to warm up on Monday if
everything comes together. The 75th percentile running about 01-15
degrees higher than the NBM, so leaned on the 75th in many areas
with the expectation that melting today and Sunday will lead to a
decent amount of bare or nearly bare ground. This should pretty much
eliminate the snow on the ground in most locations.

Fairly strong northwest flow aloft remains in place into Tuesday
with another wave expected to move through the area. Once again
moisture will be limited as will instability so the threat for more
than a few hundredths of an inch of rainfall are very low(about 10%
or less). Temperatures will again be in the 50s in most locations.

The parade of waves continues Thursday into Saturday but timing and
strength start to see more disagreement. The main story here is
northwest flow, likely struggles with moisture so only lighter
amounts of precipitation. The good news is the mild temperatures
continue with highs in the 40s and 50s. While the models still hint
at some colder air into the weekend, they have back off on how cold
and also shunted it a bit father east which would hint at less time
spent in the colder air.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 520 PM CST Sat Feb 22 2025

With snow melt across the area today and light winds overnight,
there will be a low chance (20% or less) of patchy fog
development later tonight. With low confidence, did not include
in TAFs. Otherwise, VFR conditions are expected through the
period. Winds will be light and variable tonight, then increase
out of the southwest on Sunday afternoon.

&&

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

&&

$$

DISCUSSION...08
AVIATION...JM