100 FXUS63 KABR 202313 AFDABRArea Forecast Discussion National Weather Service Aberdeen SD 613 PM CDT Sat Sep 20 2025
.KEY MESSAGES...
- Focus turns to fog potential tonight into Sunday morning, mainly across central and north central South Dakota. Visibility may be reduced to below 1 mile at times.
- Temperatures are expected to warm up on Sunday, with highs reaching the upper 70s on Monday, around 5 degrees above normal. Highs will become near-normal by the middle of next week.
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.UPDATE... Issued at 611 PM CDT Sat Sep 20 2025
So far no major changes to the forecast. Focus is on stratus in the east eventually lowering while for central/north central SD concern remains fog formation.
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.SHORT TERM /THIS EVENING THROUGH SUNDAY NIGHT/... Issued at 237 PM CDT Sat Sep 20 2025
At 2 PM CDT, skies are partly to mostly cloudy over most of the forecast area. Temperatures have been slowly warming through the 60s into the low 70s on north-northwesterly winds generally at or below 10 mph. There have been occasional rather light blips on radar where sprinkles/very light rain showers have been trying to develop across northeast South Dakota into west central Minnesota this afternoon.
An upper level low/longwave troughing will be over Minnesota and the eastern Dakotas during the period, while weak surface high pressure over the CWA lingers into Sunday night. Ensemble cloud-cover guidance shows appx the western half of the CWA clearing of this evening/overnight, while remaining, for the most part, in tact across the eastern half of the CWA. Noticing the HRRR/HRRRTL and RAP/RAPTL guidance sets were showing lower visibility/fog developing across the west tonight, where the sky is forecast to be clear. So, leaned on that guidance and continuing the mention of fog later tonight/early Sunday morning mainly across the western half of the CWA. Looking at the RAP model in BUFKIT for any drizzle/lower visibility potential across the eastern third of forecast zones (the Prairie Coteau over into west central Minnesota) tonight, but not seeing the type of deep/saturated stratus layer signal in the model soundings that favors drizzle. So, at this time, not incorporating any drizzle/reduced visibility over that area of the CWA for tonight.
Dry, with increasingly sunny skies, and near to slightly above normal temperatures are anticipated on Sunday throughout the CWA.
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.LONG TERM /MONDAY THROUGH SATURDAY/... Issued at 237 PM CDT Sat Sep 20 2025
Monday morning, we are sandwiched between 2 upper level troughs, one over southern Ontario and the other over western MT. This second low moves south late Monday before heading pretty much straight east across KS. The 850mb low for this system moves across western SD on Monday. We then are in northeast upper level flow until that low sinks farther south and we move into more north to northwesterly flow Thursday. We stay in this pattern through the end of the period.
There`s not much active weather during the period. With that low on Monday there are some 20-30% PoPs mainly in Stanley, Jones, and Lyman counties Monday evening, but that`s it through the end of the period. Accumulations are expected to be light, maybe a couple hundredths of an inch. Temperatures through the long term will be right around average with highs in the 70s.
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.AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 611 PM CDT Sat Sep 20 2025
Terminals KABR,KATY,KPIR,KMBG
VFR conditions initially. For KPIR/KMBG mostly clear skies and light winds means fog formation. In the east, with low cloud cover, CIGS will eventually drop to MVFR. Winds generally light and with little consistency in direction.
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.ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. &&
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UPDATE...07 SHORT TERM...10 LONG TERM...13 AVIATION...07
NWS ABR Office Area Forecast Discussion