670
FXUS63 KFSD 011942
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
242 PM CDT Sat Jun 1 2024

.KEY MESSAGES...

- Monitoring for a potential severe weather outbreak later
  Sunday into Sunday night. Not a cut and dry threat. May see
  some isolated stronger storms early morning, some slightly
  stronger/severe storms early to late afternoon, then the
  strongest more severe storms very late afternoon into Sunday
  evening/night.

- Tuesday may be the next chance for severe weather, but still
  some question marks, the main one being a potential MCS late
  Monday night into Tuesday morning which could push the deeper
  instability south and limit Tuesday afternoon potential.
  Models also starting to hint that the overall system will come
  out more quickly.

- Quiet weather and seasonable temperatures are expected to
  prevail mid to late week.

&&

.DISCUSSION...
Issued at 241 PM CDT Sat Jun 1 2024

A quiet afternoon and evening is expected for the area as
instability remains mostly bottled up to the southwest, at least
through about midnight. A very isolated storm could develop around
Gregory or Chamberlain this evening but confidence is low. After
midnight some elevated instability in the form of CAPE values of 500-
1000 J/kg will spread across the area. With limited shear the severe
threat will remain low and likely just looking at dime to quarter
sized hail as the main threat. The better threat for this may
be in far southeast SD into northwest IA where the stronger LLJ
exists.

By Sunday morning this activity, if it develops, should exit the
area. Another cluster of storms will be possible late morning into
early afternoon as a lead piece of energy aloft moves to the
northwest and some additional elevated instability increases. Some
hints of 1500 J/kg of CAPE or so with a bit better shear so possibly
some isolated severe storms with hail again the main threat but some
wind would also be possible. These storms into early to mid
afternoon could produce hail to half dollars and wind gusts to 60
mph. The better chance for severe weather should come after about 6
pm with an incoming cold front. Plenty of instability (2000-2500
J/kg) and shear (0-6km bulk shear 30-40 knots) so just a matter of
getting storms to develop if the earlier activity does not disturb
the daytime heating. The strongest storms will likely develop just
west and southwest of the area which may leave the largest hail
threat outside of the area. Some hints that the storms will
transition to linear after about 7-8 pm and potentially see the
biggest problems with the strongest winds near and south of the
Missouri River, then possibly into northwest IA after 10 pm or so.
For now the main threat for the largest hail would be near and west
of the James with the highest threat for winds of 70 mph south of I-
90.

Monday should be a pretty nice day behind the exiting system with
lighter winds and highs in the 80s. Maybe a bit of humidity
lingering with the recent rains and lighter winds expected.

The models appear to be coming to more agreement on a faster front
Tuesday, so starting to look like the better chance for showers and
thunderstorms will be later Monday night into Tuesday morning. Maybe
some lingering threat near and east of the Buffalo Ridge. The
overall severe weather threat looks marginal with limited
instability and a pretty poor shear profile. Regardless looks like
another good chance for rainfall.

Dry and seasonally mild weather is expected Wednesday into Saturday.
Fairly strong northwest flow aloft is expected with persistent
ridging across the Rockies and low pressure over the Great Lakes
region. This will keep any deeper moisture and instability
suppressed well to the south. Lows should mostly be in the 50s with
highs in the 70s to lower 80s.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1205 PM CDT Sat Jun 1 2024

Overall VFR conditions are expected through most of the period,
outside of showers and thunderstorms. Scattered MVFR ceilings in
northwest IA should dissipate by about 20z today. Late tonight
scattered showers and thunderstorms will be possible and
continue into mid morning Sunday. Near the end of the period a
few stronger storms will be possible, but the majority of that
activity will likely hold off until mid Sunday afternoon into
Sunday night. Some of those storms will likely be severe.

&&

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

&&

$$

DISCUSSION...08
AVIATION...08