180
FXUS63 KABR 161953
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
253 PM CDT Sat May 16 2026

.KEY MESSAGES...

- Showers and thunderstorms returning starting late tonight,
  continuing through Sunday, with rain persisting into Monday.

- Slight Risk (2 of 5) mostly focused across northeast South
  Dakota and west central Minnesota Sunday afternoon/evening.
  Marginal Risk for severe weather (1 of 5) includes parts of
  the northeast and central South Dakota. Main threats are large
  hail and a tornado or two.

- Colder air returns Monday through Wednesday, with high
  temperatures around 15 to 20 degrees below normal.
  Temperatures Wednesday morning may drop to near or below
  freezing.

&&

.DISCUSSION...
Issued at 253 PM CDT Sat May 16 2026

After today`s relatively quiet conditions, an active pattern will
begin to set up across the Northern Plains and Upper Midwest late
tonight into early next week. Sfc ridging nudging southward from the
center of the high in southern Canada has led to another dry day
across the forecast area. Winds have been more tolerable today
compared to the previous couple days, but they aren`t exactly non-
existent. Still seeing gusts between 15-25 mph with some locally
highest gusts in places like our southwest zones(south central SD)
and northeast zones(northeast SD/west central MN). The combination
of these winds and low RH values are leading to near critical fire
weather conditions on both ends of the CWA. And, if they haven`t
quite yet, it`s expected they will the as the afternoon hours
progress. Improvements on both ends are expected by early to mid
evening as winds/RH improve across west central MN and RH`s recover
across central SD.

Attention will then turn to a well organized storm system that`s
currently taking shape southwest of our region today. As an upper
trough axis continues to dig into the Rockies, lee side low
formation will take place across the Front Range/Northern High
Plains later today into tonight. This system is progged to shift out
into NE on Sunday with an inverted trough extending north into
western/central SD. This is all expected to gradually track into
eastern SD and western MN Sunday afternoon and Sunday night.
Guidance still progs a series of shortwave energy rotating northeast
into our region over the course of Sunday into Monday. CAM solutions
keep us mostly dry in our forecast area until around 06Z. The first
wave and associated precip is expected to arrive into central SD
early Sunday morning and then track northeastward through the pre-
dawn and post sunrise hours. Some of the CAMs are suggesting that
this activity may/may not be a solid coverage of showers and
thunderstorms as it comes into our western/southwestern zones. At
any rate this should track northeast of the CWA by mid-late morning
with a possible break in the precip from late morning through early
afternoon.

By Sunday afternoon, the air mass become more unstable with time,
especially across southeast SD and our far south/east zones. BUFKIT
soundings suggest that a good portion of our forecast area may
status over during the morning hours leading to more stability while
our far south/east zones become more unstable. KATY`s forecast
sounding shows a period of elevated CAPE during the mid afternoon to
early evening hours. This would coincide with SPC`s Slight Risk (2
of 5) across east central SD and west central MN. Primary threats
still remain large hail with damaging winds, locally heavy rain and
and an isolated tornado as secondary threats in those areas.
Guidance progs a line of convection forming by late afternoon across
those zones before shifting it off into southeast SD/western MN by
the early evening hours. There should be another break in the precip
from Sunday night into Monday morning before the next upper wave and
secondary low pressure system track southeast of our region. This
will provide another good opportunity for rainfall Monday afternoon
through Monday night. Expect all of this activity will remain
general showers and thunderstorms as the main threats for severe
weather will be shifted farther east and south of us by that time.

Temperatures do take a decent plunge beginning Monday as that system
rain system rotates through the region. Below normal temperatures
for both daytime highs and overnight lows are expected through the
middle of next week. High temperatures in the 40s and 50s both
Monday and Tuesday and overnight lows in the low to mid 30s Monday
night into early Tuesday and again Tuesday night into early
Wednesday will be possible. If we see those chilly temperatures at
night, given the right conditions, there will be areas of frost to
contend with across most of the forecast area.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1245 PM CDT Sat May 16 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are expected to prevail the remainder of today
into this evening. North to northeast winds this afternoon will
become east to southeast during the latter half of the afternoon
at KPIR/KMBG and at KABR/KATY late this evening into the
overnight. KPIR/KMBG terminals will see wind gusts this
afternoon up to 25 kts and then essentially remain steady or
increase further overnight into Sunday morning. The stronger
winds will spread east overnight into KABR/KATY and persist
through the end of this forecast cycle. Showers and
thunderstorm chances will increase from southwest to northeast
overnight and persist through the morning hours. MVFR cigs move
into KPIR/KMBG around sunrise Sunday morning and spread east
into KABR/KATY by mid-late morning. IFR cigs will also be
possible late in this TAF valid period.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Red Flag Warning until 10 PM CDT /9 PM MDT/ this evening for
     SDZ033>036-045-048-051.
MN...None.

&&

$$

DISCUSSION...Vipond
AVIATION...Vipond