textproduct: Aberdeen

KEY MESSAGES

- There is a 50-80 percent chance of 1/2 inch or more rainfall occurring Friday into Friday night.

- Turning much warmer Sunday through next week, around 10 to 20 degrees above normal, with highs in the 80s to near 90.

UPDATE

Issued at 824 AM CDT Thu May 21 2026

So far, just a few pockets of sprinkles activity this morning. Low level moisture return flow really starts ramping up later this evening. No changes planned, at this time, to the today period forecast.

UPDATE Issued at 615 AM CDT Thu May 21 2026

UPDATE for 12Z Aviation discussion

DISCUSSION

Issued at 205 AM CDT Thu May 21 2026

Weak mid level warm advection and subtle shortwave responsible for light showers and sprinkles this am, which will lift northeast. Otherwise we maintain a gradient with winds out of the south gusting to 20 to 35 mph.

As for the wave Friday, timing is late tonight west river with some convective nature but really just skinny CAPE in modest shear, which weakens with loss of daytime heating. Some of that might leak into the Missouri valley before dissipating. After 06Z a more consolidated (24 hours ago it was 2) negatively tilted wave lifts up across the area. CAMS take most of the day Friday to lift this system up across the CWA and it may take the northeast until early Saturday before everything has lifted north. The 25th percentile is around 1/4 inch west river to 1/2 inch in the northeast while the 75th is closer to 1 inch so still a bit of range. Just some skinny or shallow CAPE depending on model and location, so overall assessment is mainly just rain/showers with little thunder.

Thereafter, there is a secondary wave aloft 12Z Saturday overhead. This, and daytime heating may lead to additional light shower activity. NBM is dry at this time, something to watch.

We have brief zonal flow overhead/upstream for Sunday/early Monday, with flow becoming southwesterly aloft as a trough deepens across the Pacific Northwest. This increasing heights and temperatures aloft translates to warmer conditions for Sunday - Thursday. 700mb temperatures increase to +6 to +10C, about a standard deviation above climo. High temperatures that timeframe still 10 to 20F above climo.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 615 AM CDT Thu May 21 2026

Terminals KABR,KATY,KPIR,KMBG

VFR conditions will continue over the next 24 hours at ABR/ATY. MVFR to potentially IFR ceilings will return after 06Z Friday. Winds will gust 20-30kts through the day today, with the weakest winds at ATY.

ABR WATCHES/WARNINGS/ADVISORIES

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