FirstWarn Weather

Live in St Charles county or nearby? Call Canyon for mobile car detailing.

First Warn Forecast: Saturday, May 23, 2026

First Warn Headlines
Scattered showers and thunderstorms will develop later today and continue tonight.
Severe weather is not expected, but locally heavy rain and lightning are possible.
Memorial Day weekend stays warm and somewhat unsettled with additional pop-up storms possible at times.
A more active pattern returns next week with repeated afternoon and evening storm chances.

A warmer and more humid air mass is settling back into Missouri and Illinois today as temperatures climb into the upper 70s and lower 80s across the St. Louis Metro, Central Missouri, Southeast Missouri, and Southern Illinois. Clouds will increase through the afternoon as scattered showers and thunderstorms begin developing from west to east.

The overall severe weather threat remains low today due to weak wind shear and limited atmospheric organization. However, a few stronger storms may still produce brief downpours, gusty winds, and frequent lightning. Some communities could pick up localized rainfall totals between 1 and 2 inches where storms repeatedly move over the same area, though many locations will see much lighter totals.

The greatest coverage of showers and thunderstorms appears likely this evening and overnight, especially along and near the I-44 and I-70 corridors. Rain and storms will gradually shift eastward toward sunrise Sunday.

Sunday and Memorial Day are shaping up fairly decent overall with near seasonal temperatures and a mix of clouds and sunshine. A few isolated afternoon showers or thunderstorms may redevelop, mainly south of I-44 across portions of Southeast Missouri and Southern Illinois, but widespread washout conditions are not expected.

Looking ahead into next week, the weather pattern becomes more summer-like. Temperatures will remain near to slightly above average with increasing humidity levels. Multiple rounds of scattered afternoon and evening showers and thunderstorms are expected Tuesday through the end of the week. While widespread severe weather is not anticipated at this time, slow-moving storms could bring pockets of heavy rainfall.

Have a great and safe Memorial Day weekend, and keep the umbrella nearby. Spring in the Midwest is once again reminding us it refuses to sit still for very long.