827 FXUS63 KABR 140208 AFDABRArea Forecast Discussion National Weather Service Aberdeen SD 908 PM CDT Mon Oct 13 2025
.KEY MESSAGES...
- There is a 50-70% chance of rain late tonight through the day Tuesday. Areas south of U.S. Highway 212 have a 60% chance of receiving 0.10" of rain or more.
- There is a 20-40% chance of light rain Wednesday (accumulations of a few hundredths) before chances increase to 50-80% Thursday. Heaviest rainfall is expected in central SD with a 75% chance of 0.25" or more.
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.UPDATE... Issued at 902 PM CDT Mon Oct 13 2025
No major changes in regards to timing the onset of light shower activity, which is just starting to get going on radar in central/south central South Dakota. Ceilings look to be around 10-12kft, meaning with the returns over the area being pretty light, we`re probably seeing little more than sprinkles if they are in fact reaching the ground at all. Temps have stalled, though with northeasterlies and dewpoints around 40 when precipitation hits could see temperatures drop a few more degrees due to evaporational cooling.
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.DISCUSSION... Issued at 203 PM CDT Mon Oct 13 2025
The surface ridge that dominated our area is shifting northeast, from the center of high pressure over southern Saskatchewan. The main concern over the next 24 hours is light rain moving in from the southwest as a lee trough organizes at the surface and energy moves in on the southwesterly flow at 500mb. The initial concern will be how much dry air will remain from the exiting surface high. Also, forecast solutions have shifted some of the precipitation to our south compared to 24 hours ago. There is still at least a 60% chance of 0.10" of rain or more southeast of a line from Pierre to Aberdeen to Sisseton. Little to no accumulation is expected over north central SD. Southeasterly winds will be on the return Tuesday, with gusts 25-30mph over central SD. Cooler air will remain overhead, with 850mb temperatures of 4-9C by late Tuesday afternoon. Plenty of clouds and light rain should keep high temperatures in the upper 40s to low 50s.
Any break from precipitation will be short lived (or at least reduced) Tuesday night through Wednesday. The surface trough to our west will shift across southwestern SD to northeastern CO by 06Z Thursday, while the 500mb low ejects northeast across UT through MT both increasing the moisture plume into SD/western MN. The EFI shift of tails highlights the potential for well above normal temperatures Thursday morning, which look to be in the 49-56F. Normal lows this time of year are in the mid to upper 30s. Highs Thursday should briefly jump back into the upper 60s to low 70s. The slow moving 500mb low will shift across ND by midday Friday, becoming stacked with the surface low as it wraps up. Relative humidity will be high, at or above 60% each afternoon Tuesday through Thursday. The focus for the highest precipitation for the second half of the work week will be central SD, with a 75% chance of 0.25" or greater over north central SD while around 40% elsewhere in the forecast area. At this time most of the precipitation looks to fall early Thursday morning through Thursday evening. The SPC Day 3/Thursday outlook highlights our far southwestern counties in the Marginal Risk, and a southern extent to this are looks reasonable at this time.
Frost of potential freeze conditions will return Saturday morning, Sunday morning, and again Monday morning. The surface ridge will be mainly overhead on Sunday, with no distinctly light winds to accompany any of those mornings. Still, the lowest temperatures are forecast Sunday morning, with confidence decreasing as the 25-75th percentiles for temperature increase Sunday on. There is a 50% chance of lows Sunday morning being at or below 32F, particularly over much of Corson and Campbell Counties through western Dewey Counties. The chance of 36F or below increases to 50% or greater over all but our west central MN Counties.
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.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 619 PM CDT Mon Oct 13 2025
Terminals KABR,KATY,KPIR,KMBG
With a system coming in, CIGS will gradually lower over the course of the next 18 to 24 hours going from VFR to MVFR and possibly IFR. VISBY should stay mostly VFR to MVFR with shower activity that will be rather scattered in nature through the course of the system moving overhead. Best chance for consistent moisture and thus reductions in VISBY are at KATY.
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.ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. &&
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UPDATE...07 DISCUSSION...06 AVIATION...07
NWS ABR Office Area Forecast Discussion