textproduct: Aberdeen

KEY MESSAGES

- There is a Marginal Risk (Level 1 of 5) for severe weather this evening over eastern South Dakota. The main threat will be wind gusts of 60 miles per hour and one inch hail.

- Another Marginal Risk is in place for storms developing Monday afternoon and evening. The main severe threats during that time frame will be hail of 1 inch in diameter and wind gusts of 60 to 70 miles per hour.

- Temperatures roughly 5 to 10 degrees above normal (highs in the upper 80s to low 90s) are expected through at least the start of next week. There is potential for a cooldown closer to normal (highs in the mid 80s) by mid-week.

UPDATE

Issued at 621 PM CDT Sat Jul 4 2026

Updated the forecast this evening to increase pops between the Missouri and James River valley where widespread storms have developed this afternoon.

Updated aviation discussion below.

DISCUSSION

Issued at 153 PM CDT Sat Jul 4 2026

Weak troughing is currently in place across the northern plains with overall weak mid-level impulses traversing eastward. A few storms, marginally strong, have developed or continue to develop over central ND, north central MN, NW Iowa, and south central SD. The reason for mentioning these storm areas is to highlight the low forecaster confidence with regards to pops and thunderstorms the rest of the afternoon and evening. Cams have mostly failed to capture the morning convection across Jones county, where MRMS indicated subsevere hail at times.

CAMS do show convection developing later this afternoon and evening over southeastern ND and northeastern SD, where a weak frontal boundary, mostly uncapped environment is located. Meso analysis from SPC shows 2K J/kg of ML cape, with extremely limited effective and deep layer shear. The environment is supportive of pulse thunderstorms, with marginal to low end severe hail and winds possible. With locations along and east of the James River in the Marginal Risk today, have kept 20-30 pop in the forecast through this afternoon and evening. The NCAR ensemble CAM viewer suggest a low severe potential near Sisseton and east into Minnesota.

Later tonight through Sunday night should be mostly dry with above average temperatures. There could be patchy to areas of fog early Sunday morning. The weather pattern becomes active again early next week with a broad upper level trough over the southern Canadian prairies, with increasing LLM into the forecast area. Surface based cap values above 2K J/kg, modest deep layer shear should support strong to severe storms, primarily Monday evening and through the overnight hours. Upper level capping may limit convection during the daytime hours in this CWA. The upper level trough slowly crosses the region through midweek with additional chances for severe weather.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 621 PM CDT Sat Jul 4 2026

Terminals KABR,KATY,KPIR,KMBG

Widespread thunderstorm activity has developed between the James and Missouri River Valley. As of now, the storms appear to be missing all terminals. Confidence for thunderstorms impacting any particular taf site is low, thus have kept the mention out of the tafs. There could be patchy to areas of fog during the morning hours on Sunday.

ABR WATCHES/WARNINGS/ADVISORIES

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