textproduct: Aberdeen

KEY MESSAGES

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

- Isolated storm (10-20%) this afternoon/evening/early overnight. A Marginal Risk (level 1 of 5) extends into Jones and Lyman Counties. Threats are hail to 1 inch and wind gusts to 60 mph.

- Next best chance for moisture (30-60%) in the form of scattered storms is late Saturday/early Monday.

DISCUSSION

Issued at 1257 PM CDT Thu Aug 6 2026

Southerly flow out ahead of a weak trough across north central South Dakota early this afternoon, with 60 dewpoints out ahead and 30s/40s to near 50 dewpoints coming in from the west. Winds on the west side of the trough are only at 10 to 15kts so despite rh% dropping to around 10%, no need for Red Flag.

Regarding smoke, with return flow today the current airmass contains little to no low level smoke. Likewise, little to no smoke is depicted in the post frontal environment in the HRRR either. The Pacific Northwest will remain the source region of concern over the next several days, which is typically not favorable for low level smoke due to mixing as it crosses the Northern Rockies. Aloft, this is a very favorable source region especially in this northwesterly to westerly zonal flow pattern which persists through most of the forecast period (through the middle of next week).

So for today, looking at some weak convection already but still considered elevated. CAMS continue to support an isolated cell or two in the afternoon across central/northeast South Dakota, but NAM BUFKIT profiles suggest its still overall capped in this area, with the trough well back to the west of where they are generating convection. Just added a 20% probability of a storm and will leave it at that.

A cold front gets a little better organized tonight as it shifts though the area. This does two things 1) better forcing for isolated convection and 2) increased low level flow. Aside from low POPs there isn't much left to say about convection. If we have any fires this evening then the winds shifting and increasing will be a concern for fire management. NBM manages wind grids well, as 1/2km winds increase to 30kts on the 'cold' advection side of the system and increases surface winds to 25 to 30kts. NBM also hints at a re- invigoration of the downslope winds this evening/overnight across the northeast.

A northwest flow regime continues more or less continuously through at least the middle of next week. Late Sunday/Monday is the next/best opportunity for moisture in the NBM, derived from a northwest flow shortwave that traverses the Northern Rockies, and combines with a plume of monsoon moisture traveling around the 4-Corners high. This flow regime also lends towards near- average temperatures and more temperate humidity.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1257 PM CDT Thu Aug 6 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions for all terminals. Isolated storm potential this afternoon for KATY too low at this time for inclusion in TAFS. Winds shift from south southwest to west and then north northwest tonight.

ABR WATCHES/WARNINGS/ADVISORIES

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