751
FXUS63 KABR 021518 AAB
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1018 AM CDT Wed Jul 2 2025

.KEY MESSAGES...

- Scattered showers and thunderstorms (30-60% chance) continue to
  move southeast across the state this am. Storms have been sub-
  severe for the most part.

- Heat and humidity are the main story today through Friday, with
  highs in the upper 80s to near 100, and dewpoints in the 60s to
  low  70s. Heat indices may top 100 degrees in a few spots
  Thursday.

- A system late Friday/early Saturday will bring relief from the
  heat and humidity in the form of storms (60-80% chance eastern
  SD/western MN). Main concern is the potential for heavy
  rainfall.

&&

.UPDATE...
Issued at 1009 AM CDT Wed Jul 2 2025

The last of the showers and thunderstorms that went through the
area early this morning has exited the CWA with satellite
indicating overall clear skies. Current temps range in the mid to
upper 70s to around 80 and dewpoints in the lower to mid 60s. No
changes made to the forecast as it remains on track.

UPDATE Issued at 625 AM CDT Wed Jul 2 2025

Aviation discussion updated below for the 12Z TAFs.

&&

.DISCUSSION...
Issued at 310 AM CDT Wed Jul 2 2025

Cluster of sub-severe storms overhead early this morning with a wave
embedded within northwest flow. This activity will continue
southeast through the morning, with CAMS suggesting a departure time
around 11-13Z. Through the day today, profiles destabilize in far
eastern SD/western MN. CAM coverage is essentially negligible, and
we are seeing increasing heights and 700mb warm advection. There is
still a weak mid-level trough in the area so cant rule out an
isolated weak storm.

Warm air continues to migrate into the area tonight/Thursday. NBM
25th/75th box and whiskers range for high temperatures tomorrow is
closer to about 5F now, though we are still falling at or below the
50th percentile for deterministic NBM highs Thursday.  We still
maintain a bit of a south southeast wind component, and the other
wrinkle is that the NAM has some mid-level moisture across the
northern portion of the state which could impact daytime heating.
NBM heat index values are close to +100 in a few spots but not
widespread enough for headlines at this point. This is generally in
line with the deterministic HREF values of upper 90 heat index
values. Probabilistically however, the HREF still gives us a 40-70
percent chance of exceeding 100F heat index values mainly up through
the James valley.

Friday, temperatures are again into the 90s, and we still remain at
the 50th percentile or less for highs. Surface winds are more south
southwesterly ahead of a surface front, meaning we will probably
overachieve for highs, though it would be a wash in regards to heat
index values with that wind trajectories greater mixing potential.
With that mixing, despite warm temperatures aloft, NAM suggests that
the CAP isn`t going to be so strong that the front will go through
dry. As for thunderstorm activity, 0-6km shear is relatively weak
peaking at less than 30kts. PWATS remain 2 standard deviations above
climo, above 1.75". And yes, while 700mb temperatures are a standard
deviation above climo, 500mb temperatures are closer to 2 standard
deviations, resulting in weak mid-level lapse rates which will
further limit severe weather potential. With weak flow and a rich
airmass expect the main threat will be heavy rain.

The rest of the long term remains active with seasonal temperatures
thanks to a constant parade of waves embedded within wobbly zonal
flow.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 625 AM CDT Wed Jul 2 2025

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are forecast through the TAF period. Scattered
SHRA/TSRA continue to move southeast across the region, but are
beginning to exit and should be departing KPIR/KATY terminal space
at the start of the TAF period, so no mention of this at this
time.


&&

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

$$

UPDATE...MMM
DISCUSSION...07
AVIATION...TMT