Gettysburg, South Dakota Weather Forecast Discussion

647
FXUS63 KABR 240442
AFDABR
Area Forecast Discussion
National Weather Service Aberdeen SD
1142 PM CDT Tue Sep 23 2025
.KEY MESSAGES...
- Patchy fog is possible Wednesday morning over northeastern SD
  and west central MN.
- Periods of smoke aloft will continue over the forecast area
  through at least Wednesday.
- Dry and quiet conditions are forecasted across the region
  through the weekend, with high temperatures about 5 to 10
  degrees above normal.
&&
.UPDATE...
Issued at 641 PM CDT Tue Sep 23 2025
Light showers remain over mainly south central SD this evening,
mainly south of the forecast area. We`ll be monitoring for
potential fog development over northeastern SD and west central MN
near daybreak Wednesday. No significant changes are expected to
the ongoing forecast.
&&
.DISCUSSION...
Issued at 215 PM CDT Tue Sep 23 2025
As of 2pm cirrus clouds remain over the southern portions of the
forecast area with fair weather cumulus clouds starting to pop up
here and there over the CWA. Temperatures range from the lower to
upper 70s with ABR in the lower 80s with dewpoints in the mid to
upper 50s. The overall forecast well through the extended period
looks to remain dry with temperatures running about 5 to 10 degrees
above average through early next week. HRRR smoke model continues to
indicate periodic plumes of smoke plunging southwestward and is
forecasted to continue through tonight for locations mainly west of
the James River. Smoke will continue and spread eastward over the
CWA Wednesday and continue into at least Thursday. Luckily the smoke
is still forecasted to remain aloft and not expected to reach the
surface. Once again patchy fog is possible mainly over the James
River Valley and eastward into west central MN late tonight through
early Wednesday morning. NAM soundings do indicate this low level
saturation/moisture for this area. Less confidence on how westward
this fog could form.
Otherwise, a broad positive tilted ridge sits over the central and
western half of the CONUS (and its high underneath) with winds over
the CWA light out of the northeast, turning northerly by Wednesday
evening. A positive tilted trough currently extends from the central
Rockies and eastward over the central CONUS. As it continues to
track east/southeast, the southern portion of the ridge will also
shift slightly eastward through Wednesday. At the surface, high
pressure will be dominant over the region tonight and Wednesday with
the high shifting eastward over ~MN/WI by Wednesday evening. The
pattern then becomes quite wavy over the Northern CONUS into Canada
as a couple of shortwaves will pass west to east over Canada (with
ridging building behind them). Only notable surface feature will be
with the second`s wave surface low as its dry cold front, which is
forecasted to pass northwest to southeast over the CWA Friday
evening/night and high pressure moving in behind it on Saturday.
Behind this wave a broad ridge sets up and becomes quite amplified
over the region for the weekend into early next week as it shifts
slowly eastward.
Our warmest days of the week will be Thursday and Friday with highs
well in the upper 70s to the lower 80s on Thursday and even in the
mid to upper 80s possible over south central SD on Friday. 850mb
temps will be about 1 standard deviation above climo these days
ranging from +17 to +20 on Thursday and +19 to +22 on Saturday,
warmest over central SD. Behind the cold front, temps will cool back
down into the 70s across the CWA. As this second ridge builds, highs
are forecasted back into the upper 70s into the lower to mid 80s
Sunday through at least the middle of next week. Climate Predication
Center 8-14 day outlook from 9/30-10/6 indicates about a 70% chance
of above normal temps.
&&
.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1142 PM CDT Tue Sep 23 2025
Terminals KABR,KATY,KPIR,KMBG
Patchy fog is possible Wednesday morning over northeastern SD and
west central MN. This will be mainly at ATY from 11-16Z Wednesday,
and most likely from 13-14Z when visibility may get down to 1SM.
Confidence is lower on whether fog will develop at ABR, but 5SM
looked most likely from 11-15Z Wednesday. Other than morning fog,
VFR conditions are expected to continue over the next 24 hours.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
&&
$$
UPDATE...06
DISCUSSION...MMM
AVIATION...06

NWS ABR Office Area Forecast Discussion