Area Forecast Discussion
Issued by NWS Sioux Falls, SD

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102
FXUS63 KFSD 040347
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
1047 PM CDT Mon Jun 3 2024

.KEY MESSAGES...

- Scattered showers and isolated thunderstorms move from west to
  east Tuesday morning with better thunderstorm chances east of
  I-29 Tuesday afternoon. A couple of the afternoon storms may
  be strong to severe.

- Dry with windy periods Wednesday-Thursday. Lighter winds are
  expected Friday-Sunday with seasonable temperatures.

- Low (20-30%) chances for showers or a few thunderstorms
  Friday night. Neither severe weather nor heavy rain are
  expected.

&&

.DISCUSSION...
Issued at 135 PM CDT Mon Jun 3 2024

Tonight: Lead WAA begins to push in from the west and should result
in at least isolated to scattered shower and thunderstorms by the
second half of the overnight. Elevated instability generally less
than 1000 J/kg so risk for severe weather is very low but any
stronger storms would still carry some risk of small hail.

Tuesday: Cold front begins to approach the I-29 corridor by midday
and will provide for additional forcing for renewed thunderstorm
development as it slides east. Ahead of the front, MLCAPE values
between 1-2k J/kg establish and will allow for some stronger
updrafts. A limiting factor to more widespread strong/severe
activity looks to be deep layer shear with EBWD values generally
around or below 30 kts, perhaps lending to more pulsy activity.
Marginally severe hail likely the primary risk with perhaps a rogue
wind gust with any collapsing storm and pockets of heavier rain over
an already saturated portion of the coverage area the secondary
risks. These risks are covered by a Marginal Risk east of I-29
increasing further to a Slight Risk on the far eastern fringes of
our CWA.

Wednesday: Reinforcing push of mid level CAA for Wednesday with as
much as 35-45 kts of wind at the top of the mix layer allowing for a
breezy to wind day. A decent westerly component to the wind should
aid mixing and allow for afternoon high temperatures to still push
into the mid 70s to mid 80s.

Thursday thru Sunday: A period largely characterized by upper level
NW flow. This will keep temperatures near or a touch above seasonal
normals as the ridge axis ever so slowly pushes east with time. This
pattern also keeps significant precipitation chances low although
not zero as subtle waves running through the flow can occur,
although difficult to resolve at longer time ranges. At least minor
hints of one such wave Saturday.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1039 PM CDT Mon Jun 3 2024

Convection as of 330z in south central SD has been pulsy over
the last 30 minutes or so. If it is able to hold together, could
impact 9V9 and surrounding areas by 5z.

Otherwise, largely VFR conditions expected, with lower
ceilings/visibility possible with periodic convection chances.
Would expect most of the MVFR/IFR conditions Tuesday afternoon
east of I-29 where -TSRA coverage is expected to be greatest.
Isolated to scattered showers and storms are possible through
mid morning, with increasing coverage late morning near I-29.
Better chances will be early to mid afternoon east of I-29 as a
cold front goes through. Rain/storms end during the evening.

Winds increase overnight into the early morning hours Tuesday.
Direction overnight will be largely southerly until daybreak,
when a cold front begins to move through and shift winds to the
northwest. Winds shift through the period and could gust around
25 knots near the front. Lighter and variable winds expected
toward the end of the period.

&&

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

&&

$$

DISCUSSION...Kalin
AVIATION...SG