textproduct: Paducah

KEY MESSAGES

- A stationary boundary to our northwest will bring renewed chances of showers and thunderstorms Thursday through Saturday.

- The best chances of rain will be Thursday morning in southeast Missouri and southwest Illinois, then Thursday night into Friday morning across the entire region, then again Friday night into Saturday.

- Dry weather will return Sunday, but so will hot and humid conditions. Daily peak heat index values of 100 to 105 degrees are forecast Sunday through Tuesday.

DISCUSSION

Issued at 1256 PM CDT Wed Aug 5 2026

At the synoptic level, the region remains under the weakening influence of H5 ridging and surface high pressure across the Upper Ohio Valley. Another mid- level ridge is located across the Desert Southwest, while broad troughing is present across the northern and central Great Plains. A deep 992 mb surface low is located over Hudson Bay, with a weak/diffuse trailing cold front oriented from NE to SW across the Great Lakes and Central Great Plains.

The surface high over the Upper Ohio Valley will bring continued dry and seasonable temperature and humidity values through this afternoon. Tonight, showers and thunderstorms will develop to our west across the the Lower Missouri Valley as a shortwave trough interacts with the frontal boundary. Some of this activity (mainly scattered showers and a few rumbles of thunder) will move into southeast MO and southern IL Thursday morning before weakening. During the rest of the day into the evening hours on Thursday, mainly isolated diurnal convection will be possible.

Additional shortwaves will trigger more rounds of scattered convection very late Thursday night into Friday morning and again Friday afternoon into Saturday morning (with lingering activity into Saturday afternoon in west KY). We have been messaging a possibly low-end severe risk with this activity, but the latest CAMs are less impressive with the already meager shear values. Latest thinking is this activity will be more garden- variety summertime storms more than anything else.

By Sunday into next week, the frontal boundary will retreat to the north as H5 ridging across the Desert Southwest expands eastward into the central/southern Great Plains and Ozarks. This will mean increasing temperature and humidity levels, beginning Sunday and continuing into early next week. Right now, high temperatures are forecast to reach the lower 90s with dew point temperatures in the middle to upper 70s. This will yield daily heat index values of 100-105 degrees Sunday through at least Tuesday next week.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1256 PM CDT Wed Aug 5 2026

High pressure to the northeast will keep dry conditions over the region this afternoon into tonight. FEW-SCT diurnal CU development will continue this afternoon with bases around 5kft. Winds will be very light from the S to SW. Tonight, high clouds will thicken and lower and thunderstorms develop to our west ahead of an approaching front. A few showers may impact CGI and MVN, and PROB30 groups for showers from 12-18z Thursday. Otherwise, mid-level clouds will increase with winds becoming NE to NW but remaining very light.

PAH WATCHES/WARNINGS/ADVISORIES

IL...None. MO...None. IN...None. KY...None.