559
FXUS63 KFSD 070848
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
348 AM CDT Tue May 7 2024

.KEY MESSAGES...

- Isolated showers today, with near seasonal temperatures and
  breezy southwesterly winds. Gusts 30 to 40 mph expected,
  although an isolated higher gust is possible with any showers
  and in south central SD. Will monitor potential for a small
  Wind Advisory later today.

- More widespread rain and isolated storm chances on Wednesday.
  Although severe weather is not expected, funnel clouds and
  locally heavy rain are possible - mainly along/east of I-29.

- Warmer and mostly dry conditions move in for weekend and into
  early next week.

&&

.DISCUSSION...
Issued at 346 AM CDT Tue May 7 2024

CURRENTS: Showers and isolated storms are continuing to move out of
southwestern MN and northwestern IA early this morning. Winds are
already on the increase, with gusts through 3 AM CDT/08z around 20
to 35 mph. Seeing some breaks in the clouds across south central
into northwestern SD, but this is short lived as more cloud cover
pivots around the mid/upper low pressure. Temperatures are
holding steady in the 50s, but do expect areas in west of I-29
to fall into the mid/upper 40s by daybreak.

TODAY AND TONIGHT: Mid and upper level low continues to spin and
meander into western ND. We`ll be in westerly flow for part of the
day, with streams of vorticity advecting over the area. Expect
mostly cloudy skies today with the low off to our northwest.
Vorticity as well as some very weak instability (less than 100 J/kg)
could lead to isolated showers through the day; however, soundings
show that we may struggle a bit with saturation in this unstable
layer, so showers remain isolated and limited mention to sprinkles.
Near average temperatures with highs in the 60s to lower 70s. Winds
remain breezy today (out of the southwest by the afternoon) with
gusts 30 to 40 mph and sustained winds around 10-20 mph thanks to
strong flow aloft and a compressed surface pressure gradient. Could
see some isolated higher gusts in south central SD where mixing may
be more efficient later this afternoon, and stronger gusts may also
mix down with showers. Will keep an eye on the potential for a small
Wind Advisory in south central SD, especially if some of the these
more mixy soundings end up being reality. Winds and showers taper
off after sunset as we lose mixing. Lows tonight fall into the 40s.

WEDNESDAY: Mid and upper low wobbles back to the east Wednesday,
centering itself over our forecast area. This brings back more
widespread shower chances with isolated thunderstorms. Instability
is still fairly weak around 1000 J/kg, although some of the
more aggressive models (like the RAP) do have instability around
1500 J/kg. Severe weather looks unlikely - that said, cannot
entirely rule out some funnels and/or landspouts with showers
and isolated storms with the mid/upper low overhead. Mid level
lapse rates at or above 7 deg C/km coincident with the instability
and vorticity advection are somewhat favorable for this potential
along and east of I-29 during the late morning through the
afternoon hours. Folks should keep an eye on the forecast. Could
also see some brief and localized heavy rainfall with slower
shower/storm motion, with some rainfall totals east of I-29
possibly approaching an inch. Otherwise, less breezy with
north/northeast winds. Widespread showers/isolated storms and
cloud cover keeps temperatures a bit cooler, in the 60s. Lows
fall into the 40s once again.

THURSDAY INTO EARLY NEXT WEEK: Lingering showers into the day on
Thursday as the mid/upper low finally moves off to the south. Near
normal temps expected. A mid level wave and upper jet swing through
eastern ND and MN on Friday, which could bring back showers and
isolated storms to areas east of I-29 into the day Saturday. Ridging
begins to build across the Rockies by the latter half of the weekend,
allowing us to warm to above average temperatures with mostly dry
conditions into the early part of next week as the ridge axis slides
eastward.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1153 PM CDT Mon May 6 2024

MVFR conditions across southwestern MN and northwestern IA
continue to improve through the early overnight hours as
showers/storms trek eastward. Otherwise, VFR conditions are
expected through the period with clouds prevailing.

Winds shift from more south/southeasterly at the time of
issuance to more northwesterly by mid morning. Gusts through the
day tomorrow around 30 knots expected, with isolated higher
gusts across south central SD. Gusts are expected to decrease
after sunset.

&&

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

&&

$$

DISCUSSION...SG
AVIATION...SG