241
FXUS63 KABR 301915
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
215 PM CDT Wed Jul 30 2025

.KEY MESSAGES...

- There is a 40 to 60 percent chance of thunderstorms mainly
  throughout and west of the Missouri River Friday night and
  mainly throughout and west of the James River valley Saturday
  night. No severe weather is expected at this time.

- Surface smoke from wildfires is expected across much of the
  regionthrough Saturday. Monitor the latest from the EPA and
  state agencies, as there may be impacts for those sensitive to
  smoke.

- Highs through, at least Saturday, will be 5 to 10 degrees below
  normal for this time of year.

&&

.DISCUSSION...
Issued at 215 PM CDT Wed Jul 30 2025

At 2 PM CDT, skies are a mix of sun and clouds and smoke aloft.
There is also enough near surface smoke happening, that visibility
throughout the region has been reduced to 3-5 miles at times.
Temperatures are (or will soon be) warming into the 70s on northeast
winds around 5 to 15 mph. There may be some sprinkles/very light
rain trying to reach the ground now in Hand/Buffalo counties.
Otherwise, the forecast area is void of precipitation.

Through Thursday night, an upper level ridge will maintain a
position west of the CWA, leaving steering winds aloft out of the
northwest. Surface high pressure will influence the CWA with
dry/stable and cooler than normal (albeit smokey) air from Canada.
Best instability/shear for strong thunderstorms will be directed out
over eastern Montana/western North Dakota and down across northeast
Wyoming. The CWA should remain, generally speaking, dry through
Thursday night, barring the occasionally isolated shower or weak
(elevated) thunderstorm mainly along/west of the Missouri River
valley. Low level jets will be at a premium for the next several
nights, mainly west and/or north of the CWA, though. The HRRR/RRFS
smoke output supports continued near surface and smoke aloft over
the region through Thursday night. Low level thermal progs support
high temperatures in the 70s over most of the CWA, and NBM high
temperature (less than 80 degrees) probabilities agree.

From Friday onward, the upper level ridge will spend some time
shifting east into the Great Lakes region, with more zonal or west-
southwesterly flow aloft trying to develop heading into next week.
As the upper level ridge moves east, so does the surface high
pressure system, leaving this CWA in the pressure gradient/return
flow south-southeasterly wind pattern that ensues Friday into
Saturday. Maybe the nose of the low level jet can spend some time
over some portion of the CWA Friday night or Saturday night. But,
it`s more probable to find the nose of the LLJ developing north or
northwest of this CWA those two nights. Suffice it to say there is
enough of a rain signal in the models/ensembles Friday night and
Saturday night for likely PoPs (55% up to 65%) to persist in the
forecast. Further out in time, especially when it appears as though
the next synoptic-scale frontal boundary could be pushing through
the region by Wednesday of next week (under semi-zonal flow aloft),
precipitation chances also show up.

The latest run of the RRFS to make an 84 hour forecast shows a
continuance of the current near surface smoke and smoke aloft all
the way out into Saturday. Perhaps the southerly low level flow will
be able to help mix out the near surface smoke a little over the
weekend into next week. Will continue to monitor trends here.

Temperatures in the out periods will be gradually warming,
especially beyond Friday when the return flow pressure gradient-
driven southerly/southeasterly winds begin to develop, aiding in
mixing and heating. With the shift of the upper level ridge to east
of the CWA, better low level thermal advection can happen, with low
level thermal progs (925hpa/850hpa) in the deterministic models and
ensembles S.A. table anomalies showing enough warming throughout and
west of the Missouri River valley by Tue-Wed of next week to support
high temperatures recovering back into the upper 80s to lower 90s.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1216 PM CDT Wed Jul 30 2025

Terminals KABR,KATY,KPIR,KMBG

VFR (cigs) conditions will be trumped by MVFR visibility from
smoke throughout the TAF valid period. In fact, the near surface
smoke may cause visibility restrictions well beyond Thursday.

&&

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

$$

DISCUSSION...10
AVIATION...10