The 10-day span for Brentwood runs from a high near 41° on Sunday down to 18° overnight on Saturday. Roughly 0.41 in of rain falls over the period, with Monday the most likely wet day (68%). Wind is the one to watch: gusts to 33 mph around Tuesday. The NWS alert board for this area is currently clear. Right now Brentwood is running about 50° warmer than O'Fallon. Longer view: continental plains — big swings and a spring severe-storm season.
Brentwood, MO · Elev 479 ft · 38.62°N, 90.35°W · Missouri · Forecast computed for these exact coordinates