971
FXUS63 KABR 061540 AAB
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1040 AM CDT Sun Jul 6 2025

.KEY MESSAGES...

- There is a 20-50 percent chance for afternoon and evening
  thunderstorms on Monday, mainly across portions of central and
  northeast South Dakota and west central Minnesota. There is a
  slight risk (level 2 out of 5) for severe thunderstorms capable
  of producing localized large hail and thunderstorm wind gusts.

- The weather pattern stays active next week with additional
  thunderstorm chances by Thursday night into Friday.

- Seasonal temperatures are expected during the 7 day forecast,
  with the exception of Wednesday and Thursday, when high
  temperatures could bump back up into the low to mid 90s
  throughout and west of the James River valley.

&&

.UPDATE...
Issued at 1028 AM CDT Sun Jul 6 2025

Rain showers continue to move through south central sections of
SD this morning. This activity will continue to rest of the
morning hours and move out of our forecast area by early
afternoon. Cooler temperatures and lower humidity values will be
the main themes through the afternoon. The going forecast for the
remainder of today remains mostly on track. Outside of some minor
adjustments to PoPs and Sky grids, no significant changes are
planned at this time.

UPDATE Issued at 639 AM CDT Sun Jul 6 2025

See below for an aviation forecast discussion for the 12Z TAFs.

&&

.DISCUSSION...
Issued at 446 AM CDT Sun Jul 6 2025

As of 3AM, there are currently showers over areas west of the
Missouri River, with some storms over south central SD. This
precipitation is currently moving south while starting to dissipate.
The precipitation will move over areas just east of the Missouri
river, but it looks to stay west of the James River Valley this
morning. There is more precipitation and storms over western SD
moving towards central SD, though they look to be weakening as they
get closer. This will lead to scattered chances for mainly showers
over central and south central SD into and through the morning, with
a chance for a storm or two.

The upper-levels have semi-zonal flow over SD today into Monday,
with a weak high pressure developing at the surface moving in behind
the departing showers this morning. This high pressure, as well as a
lack of a lifting mechanism, will help to keep precipitation and
storms from developing Sunday afternoon into the overnight hours.
Additionally, the weak high pressure over the area will help to keep
winds light, with gusts mostly staying below 15 mph today.

An upper-level shortwave is forecast to move over SD Monday
afternoon, which helps to support a surface boundary moving into
north central SD during the afternoon and through the state into the
evening. Models currently show instability values of 1000 to 2000
J/kg over central and eastern SD on Monday, with some variation in
the location of the highest values. The models have adequate moisture
that moves into central and eastern SD from a tongue of moisture
currently over eastern MT/WY, however they vary where that moisture
moves over and when it start to interact with the boundary. With
models variation in a key component to storm development, it does
lower the confidence in storm timing, location, and strength. Even
with this lower confidence, the Storm Prediction Center has a slight
risk (level 2 of 5) for severe storms to develop over central and
eastern SD Monday afternoon into the evening. With bulk shear of 30-
40kts in the models, storms that do develop could be multicell or
become supercellular. Storm motion on model hodographs is showing a
movement to the east southeast around 20kts. This storm motion will
keep any storms that develop close to if not along the boundary as
the boundary pushes through central and eastern SD. This could lead
to training storms or storms that eventually take on a linear
structure, leading to a higher risk of strong winds.

An upper-level ridge looks to start moving towards SD by the mid-
week, bringing in weak high pressure to the area. This then starts
to advect warmer temperatures into central and eastern SD, which
will help to increase surface temperatures from the low to mid 80s
at the beginning of the week into the low to mid 90s Wednesday and
Thursday. While there is weak surface high pressure over central and
eastern SD, it doesn`t fully rule out precipitation and storm
chances. It is possible for a few ridge runner shortwaves to move up
over the north central plains upper level ridge, which could lead to
one or more surface frontal passages. This could generate additional
late week showers and storms. As we get closer to the mid-week, the
lack of precipitation in the forecast could change, so an eye will
need to be kept on this time.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 639 AM CDT Sun Jul 6 2025

Terminals KABR,KATY,KPIR,KMBG

VFR (prevailing) conditions are occurring and will continue to
occur at all four terminals. That being said, rain showers (with
embedded thunder) are currently moving towards KPIR and could
reduce visibility below VFR briefly under the heaviest downpours.
Precipitation (and potentially reduced visbys at times) should be
coming to an end at KPIR by mid-day.

&&

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

$$

UPDATE...Vipond
DISCUSSION...12
AVIATION...10