729
FXUS63 KABR 240942
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
442 AM CDT Tue Jun 24 2025

.KEY MESSAGES...

- Warmer temperatures are expected today with mostly dry conditions
  prevailing through most of the day.

- Cooler temperatures move back in tonight and Wednesday along
  with a 40-80 percent chance for showers and thunderstorms. A
  marginal risk (level 1 of 5) for severe weather is possible for
  central South Dakota late tonight into early Wednesday. This
  marginal risk expands east to include most of central and
  northeast South Dakota and west central Minnesota on Wednesday
  and Wednesday night.

- Drier conditions return by late Thursday through Friday as
  temperatures warm back above normal toward the end of the week.
  Increasing humidity levels by then will fuel periodic chances
  for showers and storms late Friday through the weekend.

&&

.DISCUSSION...
Issued at 441 AM CDT Tue Jun 24 2025

Cool conditions are being observed across the forecast area early
this morning with temperatures generally in the upper 40s to low 50s
thanks to sfc high pressure centered over eastern ND and northwest
MN. Skies are mostly clear, with the exception of north central SD
where scattered shower activity is moving northeast through those
zones. The day will start off rather tranquil but give way to
increasing clouds and a return to an active pattern through Thursday
as the upper flow pattern becomes more conducive to thunderstorm
development.

A shift in the synoptic pattern begins to unfold later today into
tonight. At the sfc, high pressure will slowly drift eastward,
allowing return flow and increasing low level moisture to develop.
Aloft, a persistent upper ridge remains entrenched over the Ohio and
Tennessee Valleys while an amplified upper level trough continues to
dominate the western CONUS. Between these two features, southwest
flow aloft will direct a series of mid level shortwave disturbance
northeastward across the Northern Plains. The first of these is
progged to lift across the Dakotas late tonight through Wednesday,
interacting with a quasi stationary frontal boundary draped west to
east across the NE/SD border area. Increasing low level moisture
influx will return mid 50s to mid 60s degree dew point temperatures
to our CWA late tonight through Wednesday. MUCAPE values generally
remain muted(<1,000 J/kg) across our area by late tonight into early
Wednesday with higher values across western SD. Deep layer shear is
progged to be about 35-50 kts, so the combination of the strong
shear and elevated instability will support for some strong to
severe storms. Anticipate convective initiation west of the CWA
tonight and some of this activity will stumble in central sections
of SD(our western/southwestern zones) closer to midnight tonight.
SPC currently highlights our western zones for a marginal risk
(level 1 of 5) for severe weather, mainly for the anticipated
activity late tonight into early Wednesday morning that would
include marginally severe hail and localized strong thunderstorm
wind gusts.

The pattern remains relatively unchanged on Wednesday into Wednesday
night. The sfc frontal boundary will continue to linger just south
of our area with a continued stream of shortwave energy rotating
through the area. By the time Wednesday begins our PWAT values are
progged to range from 1.5" to 2.00", with highest values still
confined to our far south and east zones into the greater southeast
portion of SD. This is about 2.5 to 3 standard deviations above
climo per the NAEFS/ENS. WPC continues to highlight our southern and
eastern zones with a marginal risk for excessive rainfall(ERO) with
a slight risk ERO just out of our CWA to the southeast for tonight
through Wednesday night. The heaviest of storms will be capable of
producing 1-2" rainfall rates, especially in those higher ERO risked
areas, so this will be something we will have to monitor in terms of
flooding potential particularly in those areas that already
experienced some flooding in mid June. SPC has expanded the marginal
risk (level 1 of 5) for severe weather into a majority of the CWA on
Wednesday and Wednesday night. Favorable instability looks to set up
farther south of our area with deep layer shear values ranging from
25-35 kts. Still, with all the substantial moisture available to
fuel storms, can`t rule out some of them turning strong to severe
with hail and strong winds the main threats.

On Thursday, a shortwave trough axis is progged to shift through the
region which will help to push the aforementioned lingering front
east and bring an end to the precipitation during the day. Low
amplitude shortwave ridging takes hold briefly giving us drier and
warming conditions by Friday and into the beginning of the weekend.
Return flow sets up again as early as Friday afternoon with
southerly low level flow. This will pull in more rich gulf moisture
with dew points climbing back into the mid to upper 60s. Another low
amplitude upper trough is progged to traverse the US/Canadian border
region this weekend. This in combination with the high humidity
values should be enough to fuel scattered thunderstorm activity
sprinkled on/off throughout the weekend.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1225 AM CDT Tue Jun 24 2025

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected through the next 24 hours. Winds
become southeast around daybreak to mid morning and turn gusty at
times around 20 kts this afternoon.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&

$$

DISCUSSION...Vipond
AVIATION...20/Vipond