154
FXUS63 KABR 271822
AFDABR

Area Forecast Discussion
National Weather Service Aberdeen SD
122 PM CDT Thu Mar 27 2025

.KEY MESSAGES...

- Elevated fire weather concerns over central South Dakota Friday
  afternoon, with developing northwest winds.

- Temperatures to continue some 10 to 20 degrees above normal
  tonight and Friday before the cool down begins Friday night.

- Precipitation moves through the region late Friday night through
  Sunday. Around a half inch of liquid is expected for parts of
  central and northeast South Dakota, and west central Minnesota.
  Mainly rain is expected to fall, but will transition to snow
  Saturday evening.

- There is a low probability (less than 20% chance) of freezing
  rain occurring during the transition between rain and snow
  Saturdayevening.

&&

.SHORT TERM /THIS EVENING THROUGH FRIDAY NIGHT/...
Issued at 116 PM CDT Thu Mar 27 2025

As of 1 PM CDT, skies are sunny and temperatures are warming
through the 40s and 50s, on their way to the 50s and 60s by the end
of daytime heating. Winds are maintaining an easterly direction
right now generally in the 15 to 20 mph range with gusts up to 30
mph.

The developing lee-of-the-Rockies surface trof will induce a shift
in wind direction to more of a southeast direction by late this
afternoon. Overnight and Friday, a surface low is scheduled to
emerge out of this lee-side trof and move southeast through the CWA.
The lee-side trof ends up taking on warm frontal characteristics,
while the trailing cold front is forecast to sweep south-southwest
across the CWA during the day on Friday. While in this WAA zone
during the first half of Friday, there could be a few spots of light
precipitation developing/moving near the ND/SD border, so did allow
for the bleeding over of some slight chance PoPs from ND down into
the extreme northern tier zones in SD. Warmest temperatures
along/north of U.S. Highway 12 are expected in the morning hours on
Friday, while areas south of Highway 12 should warm in a more
diurnal-typical fashion (warmest temps in the afternoon). Rapid
update/short term guidance is generating post cold frontal stratus
on Friday, dragging it southward across the CWA. An upper level
ridge over the CWA, as the tonight period starts, will experience
height falls such that southwest flow aloft should be taking over
when the Friday day period starts. While in southwest flow, some of
the preliminary shortwave energy governing precipitation chances
heading into Saturday looks to be kicking out of the Rockies and
spreading up toward South Dakota by the end of the Friday night
period. Ensemble-powered (GSM-based) PoPs are still showing up
during the later half of the Friday night forecast period. But, some
of the latest hi-res CAM p-type output indicates that precipitation
start time might not be during the Friday night period, at all,
delayed instead into the beginning of the Saturday day period.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 116 PM CDT Thu Mar 27 2025

System this weekend continues to be the main headline in the
extended period. Some variance in the low track has still been
observed, but for the most part is settling into a path that would
focus the highest precipitation totals over northeastern and parts
of central South Dakota. Current liquid equivalent QPF amounts range
from 0.4-0.6" through the whole event, with locally higher amounts
possible. QPF gradually decreases along a gradient moving into north
central South Dakota, but currently everywhere in the CWA is set to
receive some amount of precipitation.

There are some chances for winter precipitation expected with this
system, although the main precipitation type is expected to be rain.
Through the event, the best lift is expected to be in the upper
levels, meaning ice will form aloft and a warm layer around the 850-
800mb layer will be responsible for any melting. 850 temperatures
start in the mid single digits above freezing Saturday morning, and
are expected to cool throughout the day. As the temperatures reach
closer to zero, there may be brief periods of freezing rain
(depending on surface temperature) and then finally a change to snow
as all melting disappears from the vertical profile. The timing of
the transition will have a great deal of influence over the snowfall
totals, but it is currently expected to hold off until after the
highest precipitation rates have passed. This leads to less than an
inch of snow accumulation expected for most of the area, although
some areas may see up to two inches.

After a weak ridge and a surface high pressure build in early next
week, another low pressure center is on the horizon mid next week.
There is still a high level of variability in the track of the low
due to the time range, but it will be directly related to the depth
and progression of the incoming upper level trough. Ensemble cluster
analysis shows around a 60% chance of a favorable development
pattern over the area mid-week. Depending on when exactly the
precipitation comes in, both rain and snow will be possible, as
daytime temperatures next week are in the 40s to 50s, while
overnight lows drop into the 20s.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1223 PM CDT Thu Mar 27 2025

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are forecast to prevail through the TAF valid
period for KPIR/KMBG and KABR. KATY should also maintain a VFR flt
cat until Friday morning when some MVFR ceilings could be
developing/moving over the KATY terminal.

&&

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

$$

SHORT TERM...10
LONG TERM...BC
AVIATION...10