textproduct: Kansas City/Pleasant Hill

KEY MESSAGES

- Cooler and slightly less humid today.

- Showers and thunderstorms possible to likely late tonight into Monday morning. Locally moderate to heavy rainfall may be possible.

- Warmer temperatures (but seasonal) expected to return Tuesday and continue through the remainder of the week.

DISCUSSION

Issued at 329 AM CDT Sun Aug 23 2026

Northwesterly flow aloft remains entrenched over the region between high amplitude ridging across the Rockies and western CONUS and troughing across the Great Lakes and into Appalachia. At the surface, high pressure remains in place over the region, yielding nearly calm winds with some high clouds streaming north to south overhead. All in all a very pleasant late August day is expected today, with afternoon high temperatures only forecast to reach the lower 80s for most locations. More importantly, good mixing into a dry airmass should allow for dew points to drop to the upper 50s to lower 60s this afternoon, making for quite comfortable humidity levels. Quite a bit of mid to high level cloud cover is likely to move in by late this morning, with some isolated elevated showers possible by this afternoon across eastern KS into far western MO. However, with relatively dry low levels, quite a bit of evaporation is likely. As we head into tonight, a shortwave trough is progged to translate across the Dakotas into Iowa along the northeastern periphery of the upper ridge. Meanwhile, a southeasterly oriented low level jet will develop late tonight into early Monday morning. This will usher in moisture return, with PWATs increasing significantly from this afternoon into late tonight, primarily across eastern KS into western MO. These features should also help generate showers and thunderstorms across the region late tonight into Monday morning, however, CAMs differ considerably with respect to the exact evolution and intensity of these showers and storms. The 06z HRRR is the least excited about any flash flood potential, with total accumulations generally less than half an inch. However, the 06z NAM Nest suggests the potential for pockets of 1-2 (and perhaps more) inches, although the NAM Nest PWATs are significantly higher than other models and seem a bit unrealistic. The 06z RRFS is somewhere between the HRRR and the NAM Nest. All that to say that there does seem to be at least some low end potential for locally moderate to heavy rainfall late tonight into Monday morning, and WPC has maintained the marginal risk for excessive rainfall across eastern KS into far western MO. Convection should dissipate/exit south of the CWA by late Monday morning, with dry conditions expected for the remainder of the day and afternoon high temperatures ranging from the lower 80s across northern MO to the mid 80s elsewhere.

As we head into Tuesday and the rest of the week, the western ridge should remain in place, with northwesterly flow aloft continuing over the CWA as troughing remains over Ontario/Quebec and into the NE CONUS. This will result in afternoon highs in the mid to upper 80s through the week and occasional low end (20 to 30%) chances for showers/storms as disturbances and vort maxes translate through the northwesterly flow on the northeastern periphery of the mid/upper ridge.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 627 AM CDT Sun Aug 23 2026

Currently VFR at all terminals under some passing high level clouds with light and variable winds. High level clouds will increase in coverage by a bit later this morning, but VFR conditions are expected through the period. Isolated to scattered showers and perhaps some thunderstorms may develop overnight tonight into early Monday morning, so have introduced a PROB30 for -SHRA to handle this. Winds should remain light (6 knots or less) and variable through the period.

EAX WATCHES/WARNINGS/ADVISORIES

MO...None. KS...None.