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000
FXUS63 KFSD 242311
AFDFSD

Area Forecast Discussion
National Weather Service Sioux Falls SD
611 PM CDT Wed Apr 24 2024

.KEY MESSAGES...

- Chances for rain and storms return Thursday and persist
  through the weekend. Strong to severe storms are possible on
  Friday.

- Beneficial rainfall is possible Thursday night, with a 50-80%
  chance for exceeding a half an inch of rain.

&&

.DISCUSSION...
Issued at 255 PM CDT Wed Apr 24 2024

CURRENT/TONIGHT: Quiet conditions continue to prevail across the
region, with latest observation showing fairly light S/SE winds and
temperatures in the upper 50s to mid 60s. Heading into evening,
expect winds to primarily be out of the southeast, with gusts
gradually increasing to 20-25 MPH throughout the overnight period.
As such, expect lows remain on the milder side, as temperatures only
fall into the upper 40s to lower 50s.

THURSDAY: Upper level low over the southwestern CONUS ejects
northeastward Thursday, causing showers and storms to return to the
forecast. Should see largely dry conditions persist through the
afternoon as upper level ridging holds tight overhead. That being
said, some CAMs do suggested that a few isolated showers may be
possible after daybreak with the initial surge of WAA. Nonetheless,
with soundings showing quite a bit of dry air still in the lower
levels, think the better chances will occur during the late
afternoon/evening. In regard to winds, expect a strengthening LLJ to
result in breezy conditions across the region, with southeasterly
gusts between 25 to 35 MPH possible through the evening. May even
see a few location approach 40 MPH at times. Like today, have highs
rising into the mid to upper 60s.

As alluded to in the previous discussion, will see an elevated warm
front surge toward the region Thursday evening. This in combination
with increased moisture and broad WAA could spark some elevated
convection. While we are not currently outlook in SPC`s Day 2 Severe
Weather Risk, can`t rule out the possibility of seeing some elevated
hailers early Friday morning if all the ingredients come together.
The other aspect to Thursday night is that 850 mb moisture transport
will increase due to the strong LLJ in place, which will set the
stage for beneficial rainfall. Ensembles have slightly increased
their probabilities, now up to a 50-80% chance for exceeding a half
an inch of rain Thursday night.

FRIDAY THROUGH SUNDAY: Widespread showers and storms are expected
heading into Friday as the as the aforementioned upper level low
nudges closer to the region. As noted in SPC`s Day 3 Outlook,
portions of our area have been included in a Slight (Level 2 of 5)
and Marginal (Level 1 of 5) Risk for severe weather. That being
said, this threat remains conditional on how far the sfc warm front
can advance and if we can achieve enough diurnal destabilization to
overcome any cooling from the morning`s storms. IF the warm front is
able to reach the MO River Valley by Friday evening, believe there
would be enough instability (~1000 J/kg) and moisture in the place
to see large hail, especially with steep mid-level lapse rates in
place. Do think it`s worth noting, that like our system last
Tuesday, think there is also a non zero chance that funnels or
isolated tornadoes would be possible if a stacked low develops,
especially considering the low cloud tops in place. Again, this
threat remains highly conditional - so will continue to monitor
trends. Aside from storm chances, Friday will continue the trend of
near seasonal high temperatures in the 60s and perhaps 70s, again
depending on cloud cover. Dew points will moisten into the 50s which
will make for the first humid day across the area this Spring.

Otherwise, look for showers and storms to continue heading into the
weekend. Depending on how the upper level low tracks, may see a lull
in activity late Friday night through Saturday morning, with wrap
around showers still likely by Saturday afternoon. Model consistency
begins to wane by Sunday as yet another wave near the Rockies ejects
toward the region. That being said, most guidance generally agrees
that showers will be possible for much of the day. Similar to Friday
night, the chance of seeing severe storms will largely depend on the
waves evolution and surface front location. High temperatures look
to remain in the 50s and 60s.

MONDAY THROUGH WEDNESDAY: Dry conditions look to prevail heading
into the new week as upper level flow turns quasi-zonal. Warmer
temperatures also look par for the course, with highs forecast to
rise into the 70s Tuesday and Wednesday!

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 607 PM CDT Wed Apr 24 2024

Mid level ceilings may be bring occasional sprinkles near and
north of the I-90 corridor through 03z, but coverage is too low
to have enough confidence to include in the TAF at this time.
Otherwise VFR conditions prevail tonight with southeast winds
slowly strengthening.

An increasing southerly low level jet may introduce periods of
low level wind shear west of the I-29 corridor and near Huron
overnight. Southeast winds will ramp up quickly with sunrise,
resulting in gusts in the 20s and 30s through the day. Scattered
showers and isolated storms spread in late Thursday afternoon
and evening.

&&

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

&&

$$

DISCUSSION...SST
AVIATION...BP