Missouri and Illinois start the morning calm and cool, but a sharp shift is brewing for St. Louis as late-winter weather gears up.
Temperatures sit near 40 degrees at Lambert Airport under partly cloudy skies. Winds stay light early, but a breezy pattern develops this afternoon. Highs climb to 65 degrees with mostly sunny skies. A brief shower is possible between early and mid-afternoon.
Low humidity and gusty winds could create pockets of elevated fire weather today. Avoid outdoor burning. Conditions can change quickly in dry grasses.
Clouds increase tonight as lows fall to 31. As March begins Sunday, skies turn mostly cloudy with a high near 46. The bigger change arrives Sunday night.
Snow is likely before daybreak Monday, then a rain-snow mix develops. Light accumulations are possible, generally under an inch, but slick spots may form on bridges and overpasses along I-64, I-70, and I-44. This is classic flash-freeze season. Wet pavement could refreeze if temperatures dip toward freezing.
Monday stays cloudy with periods of rain and a high near 44. Rain becomes likely Monday night. By Tuesday, widespread rain and even thunderstorms are possible, with highs near 59. Rain chances peak near 90 percent Tuesday.
Midweek stays unsettled with additional rain likely Wednesday and highs rebounding to the mid-60s. Early March trends milder overall, with above-normal temperatures favored in the 6- to 10-day outlook.
Five-Day Outlook for St. Louis, Missouri–Illinois:
Today: High 65, slight rain chance.
Sunday: High 46, increasing clouds.
Monday: High 44, rain/snow early then rain.
Tuesday: High 59, rain and storms likely.
Wednesday: High 65, rain likely.
