textproduct: Aberdeen

KEY MESSAGES

- There is a Slight Risk (Level 2 of 5) for severe weather this afternoon and evening, mainly east of the Missouri River. Large hail of 1-2" in diameter and wind gusts of 60 to 70 mph are the main threats. An isolated tornado or two will be possible. Additionally, there is the potential for flash flooding due to heavy rainfall. Areas west of the Missouri River are under a Marginal Risk (Level 1 of 5).

- Thursday, another Slight Risk for severe weather is in effect along and south of US Highway 12. Areas to the north of US Highway 12 are under a Marginal Risk. Large hail of 1-2" in diameter will be the main threat, with wind gusts of 60 mph as a secondary threat.

DISCUSSION

Issued at 133 PM CDT Wed Jun 3 2026

As an upper-level low over Saskatchewan moves east today into Thursday, a cold front will be pushing through central and northeast SD this afternoon and through the evening. The RAP is forecasting 1500-2000 J/kg of MLCAPE over areas west of the James River during the afternoon spreading east through the afternoon into the evening. There is also forecast effective bulk shear values of 40-45kts in these areas, which will help with the development of supercells. Discrete supercells look to develop this afternoon between 2-4pm cdt in areas mainly east of the Missouri River. While these storms are more discrete, all severe threats will be possible. Mid-level lapse rates of 7 to over 8 C/km as well as favorable freezing levels are supportive of significant hail development (2+ inches in diameter). DCAPE values of 800-1000 J/kg could help get strong to severe winds to the surface (gusts of 60-70+ mph). Additionally, an isolated tornado or two cannot be ruled out. Later in the afternoon into the evening, as the cold front catches up to the storms, the storms look to become more linear in nature over northeastern SD. These storms will decrease the significant hail chances, and strong to severe wind gusts will become the primary hazard. The storms look to move out of northeastern SD and west central MN after midnight giving the area a little bit of a break. There is a risk for heavy rains in these storms as well as some flooding risk. PWAT values, of 1.2-1.4 inches, are above the 90th percentile for the area compared to climate values. Storms are forecast to not be slow moving, which does decrease the flooding potential a little bit. However, if multiple storms move over the same area or there are stronger storms, then a lot of heavy rainfall could happen and cause the rain accumulations to add up. Additionally, if storms move over areas that have recieved lots of rain in the past few days, then the saturated ground might not be able to hold very much rain and there could be some flooding potential.

After the storms move through, the rest of the overnight hours will stay fairly quiet. Calm winds over the James River Valley and other areas to the east as well as moisture left from the storms during the evening will lead to the development of some patchy fog. This fog should dissipate during the morning. During the morning, there could be some scattered showers and storms that develop over central SD.

Thursday afternoon into the evening, another front will be moving through central and northeastern SD. With MLCAPE values in the afternoon getting up between 1000-2000 J/kg and lingering moisture, thunderstorms will likely develop during Thursday afternoon into the evening. Shear values of 35-40kts will help the storms to develop into supercells or multicell clusters of storms. The SPC has a slight risk (level 2 of 5) for severe storms to develop south of HWY 12. Lapse rates of 7-8 C/km over central SD will help with the development large hail as the primary threat, with strong to severe wind gusts possible as a secondary threat. Higher low level shear values are currently forecast to stay to the southwest of Jones county, which will help to limit the potential for tornado development in central and northeastern SD. While the greatest severe weather threat will move out of the area during the late evening, there are still chances for some scattered storm and shower development overnight into the morning. There is a marginal risk for some severe storm development over northeastern SD Friday from a warm front trying to move north into SD, MN, and WI. Northeastern SD could see some isolated storm development during the afternoon that could have some hail and wind.

As a small upper-level ridge is forecast to build over SD this weekend, a surface high pressure will move over central and northeastern SD. This high pressure will help to keep showers and storms from developing Saturday. Additionally, with the warm front Friday, temperatures will get up into 80s to low 90s during the weekend.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1227 PM CDT Wed Jun 3 2026

Terminals KABR,KATY,KPIR,KMBG

Some scattered showers early this afternoon will lead to some lower ceilings over KPIR, and KMBG for a bit while other areas will see VFR to MVFR conditions. There is a slight risk (level 2 of 5) for severe storms to occur this afternoon over KMBG, KABR, and KPIR and during the evening for KATY. Once these storms move through, conditions should get better. Southerly to southeasterly winds will be possible this afternoon, with gusts of 20 to 30 mph (highest over KATY). Once a cold front moves through with the storms, the wind will switch to be coming from the northwest and then become fairly light and variable into Thursday morning. Additionally, patchy fog will be possible in the morning, which could decrease visibilities over KABR.

ABR WATCHES/WARNINGS/ADVISORIES

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