207 FXUS63 KABR 121236 AFDABRArea Forecast Discussion National Weather Service Aberdeen SD 736 AM CDT Fri Sep 12 2025
.KEY MESSAGES...
- There is a Marginal Risk (level 1 out of 5) of severe weather over the northwestern half of SD tonight and over central SD Saturday.
- High temperatures will run 5 to 10 degrees above normal through Tuesday, before returning to seasonal values.
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.DISCUSSION... Issued at 336 AM CDT Fri Sep 12 2025
Smoke still lingers over our area, showing up in the HRRR/RRFS model guidance. The EPA`s fire.airnow.gov site has shown PM2.5 aqi values in the yellow category for most sensors near and east of the MO River early this morning. The overall trend is for improved conditions smoke wise. We will keep the mention of smoke out of the forecast as it is not lowering visibility.
Taking a look at the 08Z surface map, the low pressure system stretching from southwestern SD through central NE. Out ahead of the low we have ongoing light showers and a few thunderstorms with winds out of the southeast and dewpoints in the 60s. The main concern for strong to severe storms remains to our north. Lapse rates remain impressive, but shear is set up across ND. While we do have some thunderstorms, they have been small and have had a difficult time sustaining themselves. We`ll continue to monitor the trends as these showers and storms move north-northeast around 25kts. One concern noted by several CAMs was the potential for the thunderstorms currently over northern ND (near Fort Totton/Devils Lake) to slide southeast and clip our far northeastern counties. While the storms are pushing out to the southeast, it`s unknown if they will be able to make it to our far northeastern counties. Still, we have slight chances (20%) of showers and storms lingering over our northeastern counties until nearly 21Z, but this will continue to be fine-tuned this morning. A warm layer above the surface will act to limit storm development this afternoon. 700mb temperatures will be 11-12C.
The surface low will set up across mainly southwestern to south central SD through western NE this afternoon and remain in place through much of the day Saturday. The surface low will be reinforced by an additional trough from the west-southwest, with a trough of some sort set up across SD through at least Thursday morning. Low chances for precipitation will continue, with the highest (30- 60%)being when 500mb troughs swing through Sunday and Tuesday night into Thursday.
As for the near term, dewpoints will near 70F this afternoon with temperatures topping out in the 80s, except in the low 90s over our southwestern counties of central/south central SD. Another round of storms is expected this evening west of the MO River, and overnight across central SD with the chance of precipitation increasing to 40- 70% by around daybreak Saturday. There is a Marginal Risk of severe storms over primarily the northwest half of SD on the Day 1 outlook and over central SD for the Day 2 outlook for the potential for these storms tonight into Saturday morning.
Confidence remains high in the temperature forecast through the period, with highs mainly in the upper 70s and 80s through Tuesday before a slight cool down with highs in the 70s Wednesday through Friday (or near seasonal normal values).
Overall fire weather concerns remain limited, despite the limited rain over the last couple of weeks and some drying of fine fuels (grasses). This is due to the higher dewpoints and generally light winds that are expected to continue through at least Saturday night. Near surface winds increase Sunday into Monday, with gusts 25-30 mph.
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.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 736 AM CDT Fri Sep 12 2025
Terminals KABR,KATY,KPIR,KMBG
Mainly VFR conditions are expected over the next 24 hours. While fog has been added to the forecast for around daybreak Saturday, it is expected to stay mainly east of ATY. The main question is if/when thunderstorms near PIR/MBG late this evening or more likely near or after 09Z. As confidence increases in timing and likelihood, the mention of thunderstorms will be added to the TAF for MBG/PIR.
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.ABR WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. &&
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DISCUSSION...06 AVIATION...06
NWS ABR Office Area Forecast Discussion