textproduct: Aberdeen

KEY MESSAGES

- Marginal Risk (level 1 of 5) of severe weather from 5-8 PM mainly southeast of a line from Watertown to Ortonville.

- Dry conditions are expected Friday through Saturday. A 30-60 percent chance for showers and thunderstorms will return to the area the latter half of the weekend into early next week.

UPDATE

Issued at 1041 AM CDT Thu Aug 20 2026

The ongoing forecast remains on track. Our initial round of showers has nearly exited northeastern SD/west central MN. Model consensus showers afternoon/early evening thunderstorm initiation near our south of our forecast area (marginal risk of severe weather with all modes of severe weather possible from around 5-8 PM (22-01Z). We'll continue to monitor the latest trends for this afternoon. Otherwise, a bit more of a milky sky is present due to elevated smoke from the northwest.

UPDATE Issued at 609 AM CDT Thu Aug 20 2026

Updated discussion for the 12Z TAFs below.

DISCUSSION

Issued at 208 AM CDT Thu Aug 20 2026

Conditions remain fairly quiet across the forecast area early this morning as sfc high pressure continues to drift southeast across southeast SD, southern MN and WI. Meanwhile, sfc low pressure across northern ND is shifting eastward with a trough extending south and west into western/central ND into northwest SD.

The sfc trough, more or less, will become a weak cold front that is progged to sag south through the CWA today. A 20-30 percent chance for a few showers and storms will be possible this morning across northeast SD/west central MN. Not expecting anything substantial in terms of precip or severe weather. But, the presence of a low level jet will be enough to maintain activity through the morning hours. Redevelopment of afternoon storms appear more likely just to the east and south of our forecast area. Mid-level lapse rates aren't all that impressive in our area this afternoon until you get farther south into the Central Plains. Interestingly enough, HREF ensemble paintball product hints at some afternoon convection across our eastern zones. Despite MLCAPE values of 1500-2000 J/kg and deep layer shear of 35-40 kts across our far southeast corner of the CWA this afternoon, the latest NBM along with several CAM solutions came in dry, so we'll maintain a dry forecast for now. SPC's Day 1 severe weather outlook clips our southeast corner with a Marginal Risk (level 1 of 5) this afternoon, so changes in model trends during the daytime hours will need to be monitored and modify the dry forecast if needed. Behind the frontal passage, winds will become northerly by the afternoon and turn gusty between 20-30 mph.

Sfc high pressure will build south and east into the eastern Dakotas and western MN tonight through Friday. 500mb heights will be on the rise across the Dakotas on Friday and into the first half of the weekend. This should effectively give our area a couple of dry days Friday and Saturday. Temperatures should remain at or slight above normal and humidity values will remain comfortable as dew point temperatures in the 50s to low 60s are expected. The next upper trough is progged to crash over the top of the ridge the latter half of the weekend. Return flow on the backside of a high pressure system and potential interaction with a nocturnal low level jet will kick off our next round of showers and thunderstorms across central SD on Saturday night into Sunday morning and again Sunday night into Monday morning across portions of central SD and most of eastern SD and western MN. Longer range guidance shows the potential for a cold front to pass through the region early next week that could deliver more precip opportunities to the area.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 609 AM CDT Thu Aug 20 2026

Terminals KABR,KATY,KPIR,KMBG

Overall dry conditions are forecast for the TAF terminals (along with VFR cigs) through the end of the TAF period. Winds will be out of the south and southwest before switching westerly, then northwesterly behind a cold front. This switch will occur at KPIR/KMBG this morning and KABR/KATY midday into the afternoon. Gusty winds are also forecast behind the front this afternoon, ranging between 15-20kts at KATY/KMBG. Patchy smoke is also possible over portions of south central SD this afternoon and evening, mainly affecting KPIR.

ABR WATCHES/WARNINGS/ADVISORIES

SD...None. MN...None.