253
FXUS63 KABR 110508 AAC
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
1208 AM CDT Fri Jul 11 2025

.KEY MESSAGES...

- Marginal risk (level 1 out of 5) for severe storms mainly across
  central South Dakota this afternoon and across northeast South
  Dakota into west central Minnesota on Friday. Hail up to an
  inch in diameter and thunderstorm wind gusts up to 60 mph are
  possible within the risk area on both days.

- The potential exists for a noticeable cool-down during the
  middle of next week (temperatures 10 to perhaps 15 degrees
  below normal).

&&

.UPDATE...
Issued at 942 PM CDT Thu Jul 10 2025

The overall forecast for the remainder of tonight continues to be
on track. At this time, it doesn`t appear any precipitation will
materialize in most of our forecast area tonight, so made some
minor adjustments to PoPs to account for this.

UPDATE Issued at 645 PM CDT Thu Jul 10 2025

The aviation discussion has been updated for the 00Z TAFS.

&&

.DISCUSSION...
Issued at 311 PM CDT Thu Jul 10 2025

Isolated storms are forming just south of the CWA, with some
remnants of morning convection coming in from the west. Low level
flow is southerly out ahead of a weak low, with heat index values
running into the upper 80s to mid 90s. Still a lot of CIN to
overcome this afternoon and there is a weak wave moving across the
southern half of the state. CAMS are pretty limited in convective
coverage this afternoon, owing to weak upper level support.

Convection will tag along with the weak wave across the southern
half of the state tonight, with a stronger wave up along the
Canadian/North Dakota border for Friday. Shear increases across the
norther tier of South Dakota through the day, however the CAPE is
shunted all the way down towards Watertown/Brookings by early
afternoon. CAMS still support convection as a possibility along the
front prior to departing out of the CWA, in addition to the random
smattering of convection northwest of the boundary which would
feature more stable conditions in the low levels, skinny CAPE and
that higher shear environment.

Saturday will be fairly tepid with low humidity, with temperatures
around 80 degrees as NAEFS 850mb temperatures drop to a standard
deviation below climo. As this time, with the low and upper level
flows out of the northwest, we will have to continually assess
potential for impacts from Canadian wildfire smoke. A narrow ribbon
of post frontal smoke should be noted with the system Friday,
however Saturday there is broader support for elevated smoke moving
overhead in the HRRR, though the bulk of near surface smoke looks to
hang up over North Dakota late Friday/Saturday.

The next round of heat is Sunday/Monday, under a northwest flow
regime, though  no real thermal anomalies noted in the 700mb/850mb
temperatures fields. Low level flow is weak, with a weak surface
trough stalling in the central/eastern Dakotas before washing out
Sunday. For Monday, a lee low develops out west, lifts northeast and
helps support a frontal passage and convection. Thus, the high
uncertainty for Mondays` high temperatures, with the NBM 25th/75th
range for high temperatures at 12 to 18 degrees. Current forecast
for highs is also on the lower end, closer to the 25th percentile.
That high uncertainty continues into Tuesday with a range of 8 to
14C, with the lower range across north central South Dakota where
cooler air displacement is already established. Positive news in
regards to the heat is that the 75th percentile dewpoints are only
up into the low/mid 60s to not overly  oppressive, though this is
still probably downplayed as the corn is in full evapotranspiration
mode. The cooler airmass will then dominate conditions for the
middle of next week, with NAEFS 850mb temperature anomalies about a
standard deviation below climo Wednesday and Thursday.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1208 AM CDT Fri Jul 11 2025

Terminals KABR,KATY,KPIR,KMBG

VFR conditions can be expected to prevail through most of this TAF
cycle. However, a cold front will sweep through the area on Friday
leading to scattered showers and thunderstorms. Continued with
PROB30 groups at KPIR/KMBG as they will see this activity earlier by
mid morning into the midday hours. Uncertainty still remains farther
east as far as coverage and timing goes on any showers and storms.
&&

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

$$

UPDATE...Vipond
DISCUSSION...07
AVIATION...Vipond