289
FXUS63 KABR 270158 AAB
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
858 PM CDT Sun Jul 26 2026

.KEY MESSAGES...

- Western wildfire smoke may impact visibility across the Missouri
valley and points west tonight through Monday.

- Less intense heat but temperatures still 5 to 15 degrees above
normal through at least mid-week.

&&

.UPDATE...
Issued at 856 PM CDT Sun Jul 26 2026

The Extreme Heat Warning will expire at the top of the hour.
Temperatures have been falling this evening, with most
locations seeing heat indices falling below 100. Expect that to
continue through the evening, especially as slightly drier air
moves in behind the trough tonight, which is bringing more near
surface smoke into the area for tomorrow.

UPDATE Issued at 629 PM CDT Sun Jul 26 2026

Updated for 00Z Aviation Discussion below.

Only minor tweaks to the going forecast for this evening,
largely to address the smoke moving into the area from ND and
then the limited storm potential in Hand County. First for the
smoke, been seeing visibilities down to 4-5 miles and even some
ceilings around 3.5-4.5kft in western ND and expect that has
already started to move into north central SD based on
satellite. Like the day shift, felt like the HRRR Smoke output
had a good handle on the area of thickest smoke and utilized
that for the evening update and into Monday. This increased the
coverage of the smoke in north central SD this evening, then
settled back into generally patchy smoke through Monday across
the rest of the area. As for the thunder potential, haven`t seen
too much vertical development along the CU field in
southeastern Hand and southwest to Chamberlain. Did add a very
low end slight chance (15%) to that area earlier this evening,
but with limited forcing (only weak boundaries in that area),
didn`t want to go much higher than that. So far, that seems to
be a good call and would expect the CU field to gradually
diminish with time as peak heating is lost. If something gets
going, the environment is favorable for severe threat (MLCAPEs
over 4k J/kg, limited CIN, and effective shear of 35-40kts). But
would likely be very short lived in our CWA if storms developed
with the storm motions having storms slide southeast around
20kts.

&&

.DISCUSSION...
Issued at 149 PM CDT Sun Jul 26 2026

Mid-level disturbance has pretty much cleared the CWA, with cloud
cover and showers exiting to the south and east. Plenty of sunshine
across the CWA this afternoon as temperatures rise through the upper
80s and 90s. Still several more degrees to go before the end of the
day, all the while dewpoints remain high for many areas. Quite a few
locations are already seeing heat indices from 105 to 110 early this
afternoon. No plans to change headlines and will let things expire
at 02Z this evening. Still appears there isn`t a need to extend it
at this time as temps/dewpoints on Monday are coming in a tad lower
than what we saw this weekend. This keeps forecast apparent T`s
below 100 across much of the CWA.

Also watching convection chances this afternoon. CAMs continue to
show limited potential over the CWA, but will be keeping an eye on
any developing cumulus within the weak surface trough later this
afternoon. If there is any initiation, it would be within this
trough as it eventually sets up over southeast SD.

Will need to monitor smoke trends overnight as HRRR-smoke product
shows increasing concentration of smoke aloft and at the surface
tonight through the day Monday. Satellite imagery shows quite a bit
of smoke aloft across western ND and MT, even some of this making it
to the surface as witnessed by a handful of obs from 5-9SM. Followed
trends of increasing surface smoke concentration in the HRRR to add
patchy smoke wording to portions of the CWA tonight through the day
Monday.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 629 PM CDT Sun Jul 26 2026

Terminals KABR,KATY,KPIR,KMBG

Smoke is the primary concern for much of the forecast, as it
moves into the area from the northwest tonight. Have it the
worst at KMBG, as upstream obs in ND have shown visibility down
to 4-5SM and even some ceilings at 3.5-4.5kft. So hit on that
potential into this evening, but with the loss of light
scattering heading into nighttime hours, we may not see as
reduced of visibilities. For the rest of the area, tracked the
smoke based on the HRRR smoke output and included 6SM later
tonight or tomorrow morning and through the rest of the day
tomorrow. There is the potential for storms moving into the area
from western SD tomorrow evening, but should be beyond the
forecast period.

&&

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

&&

$$

UPDATE...SRF
DISCUSSION...TMT
AVIATION...SRF