658
FXUS63 KABR 130212 AAB
AFDABR

Area Forecast Discussion...UPDATED
National Weather Service Aberdeen SD
912 PM CDT Sun Oct 12 2025

.KEY MESSAGES...

- Temperatures will fall into the low to mid 30s Monday morning
  over central SD, with frost development or freeze conditions
  possible as winds diminish overnight.

- There is a 30-50% chance of rain late Monday night through the
  day Tuesday, with the main focus over our southern counties.
  Areas south of U.S. Highway 212 have a 30% chance of receiving
  0.25" of rain or more.

&&

.UPDATE...
Issued at 856 PM CDT Sun Oct 12 2025

Line of mid-level forcing with clouds and light showers continues
to advance eastward across the CWA and is very nearly out.
Previous forecast PoPs were timed nicely and very little changes
needed there. Winds continue to be breezy/gusty for most areas,
but latest guidance continues to decrease speeds to around 5 to 15
mph by sunrise. Wind advisory was allowed to expire at 01Z. Don`t
anticipate any changes to the frost/freeze headline either as
current forecast lows still look to be in good shape. The fact
that winds don`t go completely light by sunrise brings hesitation
into dropping readings much further.

&&

.DISCUSSION...
Issued at 249 PM CDT Sun Oct 12 2025

At 19Z ABR-88D radar was showing returns over western Corson, Dewey,
and Jones Counties associated with the 850mb front(as well as a
500mb wave - with southwesterly flow continuing through 12Z Friday).
A look at SD DOT webcams showed the flat stratocumulus clouds with
little to no rain so far. The surface cold front was set up from
around Britton to Clark and Willow Lake, with the quick wind shift
to out of the west-northwest behind the front. Wind gusts on either
side remain in the 25 to 35 mph gust range, except for portions of
north central SD that have been gusting closer to 40 to 45 mph
through much of the day (where a Wind Advisory remains in effect
until 01Z Monday for Corson and Dewey Counties). The initial mid
clouds have thinned out east of Aberdeen, with the main area of
clouds now being those associated with the light rain/radar returns
over central SD. This are of precipitation should shift east of
Aberdeen-Redfield shortly after 00Z Monday. Overall precipitation
amounts look minimal, with the NAM Nest and a couple of other CAMs
indicating the potential for some enhancement to the reflectivity
over our southern counties 22-24Z this afternoon. Still, any
rainfall is expected to be less than 0.10".

Our strong winds will slowly diminish this evening and overnight. At
19Z the surface map showed the 986mb low over southern Manitoba with
the cold front draped over our eastern counties. A 1030mb area of
high pressure was set up over northern British Columbia, with a
ridge extending southeast across central MT. The cold front should
be east of our eastern SD/west central MN counties shortly after
22Z. We`ll be watching the eastern slopes of the Sisseton Hills for
some brief enhancement with the wind shift and downslope wind
enhancement, with a few gusts above 45mph. One of the most favorable
locations, Summit, has been gusting generally between 36 to 45 mph
since shortly before midnight. The surface ridge to our northwest
will push across our entire forecast area by 12Z Monday. One main
result will be diminishing winds. The cold air and lighter winds
will result in frost development over much of the area, but
particularly over central SD. While a few locations will near
freezing, the highest chance of freezing conditions by morning will
be over Corson/Dewey/Campbell Counties, where a Freeze Warning is in
effect. Elsewhere, a Frost Advisory has been issued for Brown and
Spink Counties and west. The current temperature forecast is
currently between the 25th and 50th percentiles for most locations
in the forecast area, which looks reasonable at this time. We`ll
continue to monitor for the potential of lower temperatures and an
expanding of the Freeze Warning. Highs will only be in the 50s
Monday, and struggle to even reach 50 Tuesday afternoon.

While the surface ridge will result in winds around 10mph or less
during the day Monday, it`s influence will be short lived as the
main low moves over southern Saskatchewan by late Monday afternoon
and the ridge shifts across eastern ND and MN. An are of low
pressure over WY/CO will slowly organize Tuesday and Wednesday as
the area of high pressure exits across the Great Lakes. The pressure
gradient will again tighten, with winds out of the east-southest
gusting 25-30mph over central SD Tuesday afternoon. There is a 30-
50% chance of rain late Monday night through the day Tuesday, with
the main focus over our southern counties. Areas south of U.S.
Highway 212 have a 30% chance of receiving 0.25" of rain or more.

A 45kt low level jet Wednesday night through Thursday may enhance
southerly winds over and downslope of the Prairie Coteau of eastern
SD. We currently have wind gusts forecast 25-35kts, but this may
change as the time gets closer.

Otherwise, well be watching the 500mb low over far southwestern
Canada/WA dig across CA/NV Tuesday and eject northeast to near WY by
12Z Thursday. The surface low to our west-southwest will help warmer
air surge in Thursday, with highs back into the 60s and low 70s. The
NCAR Medium-range Real-time Convective Hazard Forecasts indicate the
potential for SPC outlooks when Thursday nears, particularly to our
south and west. We currently do not have thunderstorms mentioned for
Thursday into Friday, but that may change.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 638 PM CDT Sun Oct 12 2025

Terminals KABR,KATY,KPIR,KMBG

An area of VFR mid-level clouds, along with sprinkles/-SHRA will
affect KABR/KATY at the start of the TAF period, with clouds
departing from west to east after sunset. Once these clouds leave
the region, mostly SKC conditions are then expected until Monday
afternoon when high clouds approach from the southwest. Breezy and
gusty west-northwest winds will eventually subside later this
evening/tonight.


&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...Freeze Warning from 1 AM CDT /midnight MDT/ to 10 AM CDT /9 AM
     MDT/ Monday for SDZ003-004-015.

     Frost Advisory from 1 AM CDT /midnight MDT/ to 10 AM CDT /9 AM
     MDT/ Monday for SDZ005-006-009-010-016>018-033>037-045-048-
     051.

MN...None.
&&

$$

UPDATE...TMT
DISCUSSION...06
AVIATION...TMT