118
FXUS63 KFSD 022247
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
547 PM CDT Sun Jun 2 2024

.KEY MESSAGES...

- Scattered severe storms are still anticipated late this
  afternoon and tonight. A few supercells will be possible
  mainly near and west of the James River from about 4 pm to 8
  pm, then some question marks arise as to evolution this evening
  into overnight. The big question is will there be a linear
  nature to the storms or will then remain more scattered with
  less coverage of strong winds. The latter seems to make the
  most sense given no east to west instability gradient.

- Tuesday may be the next chance for severe weather, but will
  be dependent on recovery from scattered morning convection and
  timing of a cold front pushing through the region. Favored
  area for an isolated severe threat is along and east of the
  MN/IA Highway 60 corridor.

- Quiet weather and seasonable temperatures are expected to
  prevail mid to late week. Possibly some breezy periods,
  especially Thursday and Friday.

&&

.DISCUSSION...
Issued at 211 PM CDT Sun Jun 2 2024

Still some question marks regarding the evolution of the convection
tonight. Still plenty of instability, roughly 2000-2500 J/kg, with
moderate deep layer shear around 40 knots. This is plenty to support
isolated supercells capable of producing golf ball sized hail and
wind gusts to 70 mph. One thing to watch late this afternoon and
early this evening is whether or not a marginally low LFC and some
decent turning in the low level winds could support isolated
tornadoes. The best chance for supercells, large hail and isolated
tornadoes will be west of I-29 and likely around the James Valley
and points west. Showers and thunderstorms will progress eastward
through the evening and overnight. Without a stronger east to west
instability gradient and no LLJ really impinging on the area storms
may remain more scattered instead of forming into a distinct line of
storms. This may limit the extent of the wind threat and keep it
more isolated. A linear system is not impossible, but maybe a little
less likely. After about 9z most of the activity will be out of the
area.

The next wave of interest moves onto the Plains Monday night and
should bring an area of showers and thunderstorms through. Given
marginal instability of about 1000 to 1500 J/kg and weak to
moderate shear severe storms should remain isolated. There is a bit
of a dry layer below about 700 mb which could aid in supporting some
stronger wind gusts. This threat will linger through the morning,
then with the faster timing of the front areas near and east of
highway 60 in southwest MN and northwest IA will see a short window
around mid afternoon when a few stronger storms could develop but a
good chance most severe weather in the afternoon and evening will be
east of the area.

Wednesday should be warm and windy behind the exiting wave. Suspect
wind gusts around 35 mph with highs from the mid 70s to lower 80s.

Thursday through Sunday should prove to be seasonally warm and
mainly dry. A deepening low pressure over the Great Lakes and
increasing upper level ridging across the Rockies leaves the area in
northwest flow. Suspect with the deep northwest flow each day should
be a touch breezy, especially Thursday and Friday when some upper
level energy rotates around the backside of the low pressure over
the Great Lakes.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 545 PM CDT Sun Jun 2 2024

Latest hi-res guidance suggests a complex of storms, some
possibly severe, pushing eastward west of Interstate 29 from
00Z-04Z, then east of Interstate 29 from 04Z-08Z. With winds
going light later tonight and precipitation exiting the area,
there will be some potential for patchy fog on Monday morning.

&&

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

&&

$$

DISCUSSION...08
AVIATION...JM