238
FXUS63 KABR 112344 AAA
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
644 PM CDT Sat Apr 11 2026

.KEY MESSAGES...

- Areas of fog across northeast SD tonight, with visibility down to
  below 1 mile at times.

- Warm, dry, and windy on Sunday with record/near record highs
  and critical fire weather conditions for portions of
  central/south central SD.

- Unsettled pattern early next week with thunderstorm chances
  for the eastern CWA Monday afternoon. Marginal/Slight Risk
  (level 1 and 2 of 5) for severe storms along the SD/MN border
  and further eastward more into central MN.

&&

.UPDATE...
Issued at 626 PM CDT Sat Apr 11 2026

See below for an aviation forecast discussion for the 00Z TAFs.

&&

.DISCUSSION...
Issued at 206 PM CDT Sat Apr 11 2026

Still seeing drizzle across portions of the eastern CWA early this
afternoon and expect that to continue for at least a few hours. Back
edge of the stratus deck across central SD has pushed far enough
east to clear KPIR out of the clouds. Trend for the overnight is
still for this stratus deck to eventually move eastward and erode
from the west/south into early Sunday morning. Models are showing a
pretty quick erosion by early morning as a sharp warm frontal
boundary moves northeast across the region overnight, with warmer
and drier air in its wake as winds also turn to more of a southwest
direction. Models still indicating fog across portions of the
eastern CWA as well, so left mention of that in the forecast.

Later this afternoon, there may be a few showers/thundershowers
across western SD that move northeast and perhaps approach the
western fringes of the CWA by early evening. Have small PoPs (20-
30%) for this in the grids for the evening/overnight as the warm
front moves northeast.

Focus then shifts to Sunday as we`ll be in the warm/dry air mass in
the wake of the warm front. Westerly mixing winds will increase
through the day with inverted-V soundings for most locations across
the CWA. Increased highs a few degrees beyond inherited NBM values,
which puts most places in the upper 70s to low 80s. Also lowered
dewpoints more towards NBM25, while increasing winds just a couple
knots. All this puts the southwest CWA into, or flirting with Red
Flag criteria, so went ahead and issued the warning for our
southwest CWA from 17Z to 00Z tomorrow. May need headlines for fire
wx on Monday also, as current RH/wind forecast meets, or is very
close to criteria for our southwest CWA once again.

Precip chances return to the forecast on Monday as a wave of low
pressure moves eastward along a frontal boundary which is forecast
to be located across southern SD. Potential exists for a few
thunderstorms over the southeastern CWA, but better severe storm
parameters and resultant severe storm threat looks to be setting up
further east over into MN. But, SPC Day 3 outlook does bring the
western extent of strong thunderstorm potential into the very far
eastern CWA, and CAMs do hint at some convective potential in that
area, so something to monitor.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 626 PM CDT Sat Apr 11 2026

Terminals KABR,KATY,KPIR,KMBG

KPIR/KMBG have cleared out and are good VFR. They are expected
to remain VFR through the TAF valid period. Showers/decaying
elevated thunderstorms may pass near KMBG later in the middle of
the tonight period. But, the potential/confidence of
precipitation moving over the KMBG terminal is too low to
include in the TAF right now.

KABR/KATY have been showing slow improvement this afternoon.
Satellite imagery shows low level gravity waves/cloud streets
have developed/are working on the low stratus over these two
terminals. And, with there still being a couple more hours of
daytime mixing available, the latest guidance suggesting these
two terminals will clear off this evening seems reasonable.
If/once the low clouds dissipate, expect VFR conditions to
prevail unless areas of BR/FG develop and bring VSBY down to
MVFR/IFR at times tonight. Fog development is possible but not
overly confident of it right now, as would have to ditch the low
clouds first. There is plenty of gulf moisture 40s to around 50
degrees in place right now. But, winds are not expected to be
light overnight. 00Z KABR RAOB showing a plenty strong low level
thermal inversion in place. Instead of IFR fog, VFR/MVFR fog
may happen, but thinking there is a better chance of the
moisture trapped under the inversion will reintroduce/reinforce
low stratus cloudiness later tonight.

Also of note, low-level wind shear (LLWS) will be an issue for
the evening/overnight hours into early Sunday morning and have
mention of this for all TAF sites.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Red Flag Warning from noon CDT /11 AM MDT/ to 7 PM CDT /6 PM
     MDT/ Sunday for SDZ033-035-045-048-051.
MN...None.

&&

$$

UPDATE...10
DISCUSSION...TMT
AVIATION...10