textproduct: Aberdeen

KEY MESSAGES

- An isolated storm or two (10-20%) possible late tonight into Saturday morning. A Marginal Risk (level 1 of 5) extends through south central South Dakota with the main threats being hail up to 1 inch and wind gusts of 60 mph.

- Another round of isolated to scattered (20-40%) storms is expected Saturday night into Sunday morning with the focus across northeast South Dakota and west central Minnesota. A Marginal Risk (1 of 5) extends up across this area, with the main threats being hail up to 1 inch and wind gusts of 60 mph.

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

DISCUSSION

Issued at 1239 PM CDT Fri Aug 7 2026

High pressure to the north continues to feed cool/dry air into the region. NAM BUFKIT profiles show mixed winds stalled for the remainder of the day, meaning winds have peaked. Fires remain a concern given the antecedent dry conditions and low humidity, but again the limiting factor is winds.

Regarding smoke in the upper levels, overall little change with the HRRR/RAP continuing to pump smoke out of the Pacific Northwest, send it across the Northern Rockies into the Dakotas as the upper level flow regime changes little overall. There is a little less overhead currently, but more backs in late today. Concerning low level smoke, there isn't much evidence for near surface smoke between ASOS/AWOS visibility sensors and southwest ND/western SD webcams. HRRR/RAP only bring low level smoke up to the border of the CWA for Saturday, something to watch.

Next on the list is the convective potential for tonight/Saturday morning. This is more a classic low level jet setup across western/central South Dakota with a 25-30kt southerly jet aimed at central/south central South Dakota, with westerly flow and warm advection at 700mb. 700mb temperatures are pushing +15C in the post convective airmass but out ahead its only about +9C. NAM BUFKIT profiles show quite a bit of elevated instability (3k j/kg) embedded within unidirectional west-northwesterly flow of about 40kts, though CAMS are more reserved at 2-2.5k j/kg CAPE. There is only a handful of j/kg CIN in the NAM profiles as daytime heating kicks in just ahead of convection. Thus, as storms are progressing east there could be a window for surface based convection. Convection will have to walk a fine line as those capping temperatures rapidly spread east as well. Regardless, residence time in the CWA should be short as convection presses east at 40kts into southeast South Dakota. Broadened NBM POPs in time and coverage since for the most part they were too low for a mention of weather, but stuck to just 20%.

Maybe a northwest flow wave for Saturday night/Sunday morning as well, briefly suppressing 700mb warm air aloft. Depiction of convection in the 4km NAM and NSSL WRF associated with an inverted trough into northeast South Dakota/southeast North Dakota. Even if not surface based NAM BUFKIT profiles again present us with elevated CAPE and west northwesterly unidirectional flow which is closer to 40-50kts.

NBM is still pretty bullish for Sunday night/Monday morning in regards to POPs and the respective NBM probabilities for amounts hasn't changed much run-to-run, but looking at deterministic guidance there is much less of a signal for a northwest flow type wave at 500mb. There is still a plume of moisture pivoting around the 4-Corners high from Idaho/Montana/Wyoming before ejecting into South Dakota. What you end up with is moisture above 600mb with a skinny elevated CAPE profile. Again, deterministic guidance has trended down in QPF however, and the main driver appears to be EC ensembles having more QPF in comparison to GEFS/Canadian, a trend that starts with the EC deterministic being the main model with QPF of consequence.

AVIATION /18Z TAFS THROUGH 18Z SATURDAY/

Issued at 1239 PM CDT Fri Aug 7 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions for all terminals. North winds go light, shift to southerly for Saturday. Cant rule out an isolated storm towards the end of the TAF period of KPIR but probabilities too low for inclusion at this time.

ABR WATCHES/WARNINGS/ADVISORIES

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