632
FXUS63 KABR 201048
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
548 AM CDT Wed May 20 2026

.KEY MESSAGES...

- Moisture chances increase to 60-70% on Friday. Rain amounts
generally between 1/4 to 1/2 inch and a negligible threat for severe
storms.

- Turning warmer late weekend/early next week, about 10 to 20
degrees above normal with highs in the 80s to near 90.

&&

.UPDATE...
Issued at 547 AM CDT Wed May 20 2026

UPDATE for 12z Aviation discussion

&&

.DISCUSSION...
Issued at 128 AM CDT Wed May 20 2026

Not much overall going on for the next several days. This mornings
frost while still ongoing is only for this morning and the rest of
the forecast is dominated by moderating temperatures and a pair of
systems Friday.

High pressure moves east today, with return (southerly) flow across
the state.  The gradient is about 8-12mb across the state, so a
breezy (Gusts 20 to 35 mph) pair of days.  The first shortwave of
note lifts up across the southeast part of the state headed up along
the MN/SD state line embedded within southwest flow mid-day Friday.
The second wave takes a similar trajectory just slightly to the west
Friday night. The short distance between waves means a mainly
continuous precipitation mainly east river. Profiles are moist
adiabatic/no instability with some shear, so mostly just rain. NBM
mean is between 1/4 to 1/3 for the Missouri valley to around 1/2
inch in the Watertown area. The upper trough departs, with zonal
flow aloft with increasing heights Sunday/Monday.  Thats followed by
a deepening trough across the western CONUS, all of which end up
pumping warmer air aloft into the region. 850mb temperatures still
are a standard deviation above climo, and as such Sun-Tues
temperatures are forecast 10 to 20 degrees above normal. NBM
dewpoints are also on the rise with broad/weak and sometimes
intermittent southerly flow up through the Gulf and across the
Plains.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 547 AM CDT Wed May 20 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will continue over the next 24 hours.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Frost Advisory until 8 AM CDT /7 AM MDT/ this morning for
     SDZ003-015-033-045-048.
     Freeze Warning until 8 AM CDT this morning for SDZ004>011-
     016>023-034>037-051.
MN...Frost Advisory until 8 AM CDT this morning for MNZ039-046.

&&

$$

UPDATE...20
DISCUSSION...07
AVIATION...06