textproduct: Aberdeen

KEY MESSAGES

- A Severe Thunderstorm watch is in effect for central/north central and northeast South Dakota into western Minnesota. Hail to 2" and 70 mph wind gusts are the main concerns with storms. We're also seeing heavy rainfall. As the morning progresses, the coverage of the watch will adjust as storms move southeast.

- A Slight Risk for severe weather (level 2 out of 5) for today/tonight. Timing of storms is mainly late evening and overnight. Main threats are large (1 to 2" diameter) and winds in excess of 60 mph.

- Wildfire smoke aloft is expected to persist the next several days, however there is little potential for the smoke at the surface.

DISCUSSION

Issued at 1231 AM CDT Sun Aug 9 2026

30-40kt low level jet with a weak wave aloft continues to progress across eastern South Dakota, responsible for storms in north central South Dakota at midnight. NAM BUFKIT profiles indicate about 3.5k j/kg CAPE in strong unidirectional flow of 30 to 50kts from about 2km through 8km depth. Thus, expect splitting supercell storms with a large hail threat.

For today then, surface high pressure to the north will result in a north breeze with drier air and slightly cooler temperatures. Mixed winds in BUFKIT are on average about 15 to 20kts with an east to northeast trajectory.

As the high continues east, low level flow around this feature becomes enhanced tonight, with 1/2km winds increasing to 25-30kts across mostly western/central South Dakota. Warm advection at 700mb as well for the same area. NAM shows a weak wave early this morning, with a northwest flow shortwave also clipping the northeast early Monday. There is a little bit of a disconnect between each of these elements providing for some uncertainty into the coverage and severity of storms. While not a universal outcome between CAMS, many are showing storms this evening out west river weakening before low level jet re-invigoration over central South Dakota, as well as some storms dropping into the northeast early Monday morning.

Looks like this pattern, with nocturnal storms, continues into Monday night/Tuesday morning as well.

In regards to smoke, nothing new or earth shattering, just continued elevated smoke with again a unfavorable fetch for mixing down or trapping smoke at the surface.

As for temperatures for the latter half of the work week, while we are still under a northwest flow regime, there is strengthening of an eastern CONUS upper trough, allowing for more direct flow from Canada and thus cooler temperatures, though it should be noted that the latest NBM has shifted to a less drastic cool down (raised forecast temperatures about 2-3 degrees) Thursday/Friday/Saturday.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Issued at 1231 AM CDT Sun Aug 9 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions are forecast for all terminals outside of any areas of convection this morning. Already have strong/severe thunderstorms ongoing about 15 to 20 miles north-northeast of KMBG, drifting southeastward. MVFR/IFR visbies in heavy rain, large hail (>1 inch) and strong winds (>40 kts) are all possible with early morning convection. There is also a front pushing south across the region, turning southerly winds more northeasterly through about mid-day before they settle in to more of an east-southeasterly situation by early this evening.

ABR WATCHES/WARNINGS/ADVISORIES

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