textproduct: Aberdeen

KEY MESSAGES

- There is now just a 20-30% chance of 1/4" moisture across the Missouri valley tonight into Friday morning. Negligible moisture expected for the James valley and points east.

- The probability of exceeding wind advisory criteria (45 mph) is between 20 and 50% west of the James valley Saturday.

- There is Marginal Risk (1 of 5) for severe weather Saturday. Confidence is low on storm development due to very warm temperatures above the surface. If storms do form, all hazards will be possible.

- Above normal temperatures for the weekend and next week. Temperatures are forecast into the 90s and dewpoints well into the 60s. This will push heat index values into the mid 90s with increased risk for heat related illnesses.

DISCUSSION

Issued at 236 AM CDT Thu Jun 25 2026

Another mild/pleasant day across the region today, with profiles indicating some shallow cumulus with northwest flow becoming more zonal. A system is poised to cross into the Western Dakotas by the end of the day, and as it progresses east, weakens. CAMS depict rapidly dropping off returns as a cluster of showers/rain migrates out of western into central South Dakota prior to midnight, then lifting northeast with some re-invigoration. Forecast continues to only top out around a tenth or two along the Missouri valley with negligible amounts in eastern South Dakota, which is backed up by the HREF.

We start seeing ridging follow for Friday, with mid level warm advection and 700mb temperatures increasing from the temperate low single digits to a gradient of +4C to +12C from northeast to southwest respectively. This warm advection may be what CAMS are latching onto with mid level ascent showing up as skinny CAPE above 12kft suggesting an elevated convection potential. Still, these profiles would suggest limited vertical growth and sit atop a dry very warm layer. Its also not the typical 4-corner high with elevated well mixed moisture pivoting up and out of the Desert Southwest which can come with some decent moisture potential and be tough to resolve by baroclinic models.

700mb temperatures continue to warm, with the GFS/NAM/Canadian now running around +14C Saturday morning which until we start seeing +70F dewpoints is going to be a pretty effective CAP. In our far northwest CWA (Corson/Dewey), there is a bit of weakening of the CAP in the vicinity of a southwest flow shortwave and an inverted trough. Its a good shear environment for severe weather, with the CAP being the main linchpin in convective potential.

The pattern thereafter is an upper trough over the Pacific Northwest, a strong upper ridge/high over the southeast and southwest flow aloft. A series of surges of hot air associated with elevated mixed layers coming off the Colorado Plateau move overhead for the rest of the weekend into next week. GEFS places 700mb temperatures at 1 to 2 standard deviations through the Tuesday- Wednesday timeframe. And while dewpoints are on the increase, NBM deterministic values are only peaking in the 60s Saturday/Sunday. There is a higher potential as the airmass across the Southern Plains and Gulf currently feature dewpoints well into the 70s, and the NBM does have some 20% probabilities of exceeding a 70 dewpoint Saturday and 40% Sunday. HeatRisk Sunday and into next week increases to Moderate/Major as Heat Index values across eastern South Dakota increase well into the 90s.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 537 AM CDT Thu Jun 25 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will continue through the period, with light rain starting at PIR/MBG around 09Z Friday.

ABR WATCHES/WARNINGS/ADVISORIES

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