320
FXUS63 KFSD 030852
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
352 AM CDT Sun May 3 2026

.KEY MESSAGES...

- A few sprinkles may move through portions of the Missouri
  River Valley west of Yankton this morning. The main threat
  will be localized gusty winds to 20 to 30 mph with the
  showers.

- Additional shower and very isolated thunderstorm chances are
  possible Monday afternoon into Monday night. If a storm can
  develop, wind gusts to around 50 mph will be possible. The
  better chances will be south of Highway 18.

- After seasonal temperatures into Monday, cooler than normal
  temperatures return midweek. Areas of early morning frost or
  near-freezing temperatures are possible by early Wednesday
  and Thursday.

&&

.UPDATE...
Issued at 350 AM CDT Sun May 3 2026

Evening shower activity has moved off to the east of our forecast
area, but watching a narrow band of light showers or sprinkles in
western South Dakota. Trajectory could bring this activity into
portions of the Missouri River Valley this morning, though fairly
dry sounding profiles below 7-10kft may preclude anything from
reaching the surface. If we do see any sprinkles, brief wind gusts
of 20-30 mph will be possible.

Otherwise, winds in general may be on the more gusty side across
our eastern counties this morning aided by weak cold advection in
the wake of cool front sliding southeast. Surface ridge sags into
our area this afternoon, which should allow for generally lighter
winds. However, decent mixing would support occasional gusts to
around 20 mph.

As far as temperatures, modest overnight winds and mid-high level
clouds have kept readings rather mild with 3 am temperatures still
in the 50s most areas. Should still see readings dip into the mid
to upper 40s by daybreak, but mild start will set the stage for an
equally mild day. Despite recent rains and greening grasses, have
seen temperatures overperform the NBM guidance in recent days.
With aforementioned mixing expected, decided to nudge temps/dew
points a little warmer/drier this afternoon. This yields relative
humidity levels as low as 20 to 25 percent near and east of I-29,
which could lead to localized elevated fire weather conditions in
areas where the Spring green-up is lagging. Coordinated issuance
of a Special Weather Statement in our MN counties where satellite
greenness estimates indicate this may be more of a concern than
locations farther to the west and south.

&&

.DISCUSSION...
Issued at 130 PM CDT Sat May 2 2026

A fast moving wave will track southeast into ND and MN into tonight.
This will spread some mid level moisture through the area that
happens to reside within the dgz. With some very weak instability
lifting from about 700 mb a few showers will be likely this evening.
Severe weather is not expected but with a very dry sub cloud layer a
few wind gusts to 35 to 45 mph will be possible. The better chances
will be near and east of I-29.

A weak front will settle into the area late tonight but have little
affect on temperatures Sunday. Winds will turn from the north to
more westerly on Sunday evening. Highs mild in the mid 60s to lower
70s. Model soundings indicate maybe a little patchy cumulus in the
afternoon but no instability for showers, so looking dry.

A weak wave and marginal instability, generally 500 J/kg CAPE or
lower, will move into the area Monday. A broad trough to the north
will settle south and push cooler air into the area. Near and ahead
of this front, generally south of I-90, the environment may support
some gusty winds to around 50 mph with the stronger showers or
isolated thunderstorms that may develop later Monday afternoon and
Monday evening.

Northwest flow aloft remains in place Tuesday through next weekend.
This will bring a series of waves through the area but for now
moisture looks fairly limited so the threat for more than scattered
showers and isolated thunderstorms remains low. Currently the better
chances appear to come with a weaker wave Wednesday into Wednesday
night then Thursday night into Friday with a bit stronger wave.

Outside of the shower and thunderstorm potential will be frost and
freeze potential with light winds on Wednesday morning and Thursday
morning. Fairly widespread morning lows of 30 to 35 are
expected.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1245 AM CDT Sun May 3 2026

VFR conditions expected through the period. Isolated light
showers/sprinkles linger to start the period mainly southeast
of a KMML to KFSD to KYKN line and are moving to the south and
east. This activity has been able to still bring gusts to around
25-30 kts down to the surface when it passes through, and this
will be a possibility at KSUX for the next couple of hours (30%
chance). Otherwise, LLWS concerns continue for northwest Iowa
and adjacent areas of South Dakota and Minnesota over the next
few hours.

A cold front clears the area by sunrise, turning winds north-
northwesterly area-wide this morning into the afternoon. Winds will
then gradually turn back westerly and then southwesterly this
evening. Winds gusts this afternoon top out around 20 kts.

&&

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

&&

$$

UPDATE...JH
DISCUSSION...08
AVIATION...Samet