Expires:202512271300;;296186 FPUS53 KLSX 270543 ZFPLSX Zone Forecasts National Weather Service Saint Louis MO 1142 PM CST Fri Dec 26 2025 MOZ059-062-271300- Gasconade MO-Franklin MO- Including the cities of Washington, Union, and Sullivan 1143 PM CST Fri Dec 26 2025 ...DENSE FOG ADVISORY IN EFFECT UNTIL 9 AM CST SATURDAY... .OVERNIGHT...Mostly cloudy. Areas of fog. Cooler. Near steady temperature in the upper 40s. Light and variable winds, becoming east around 5 mph. .SATURDAY...Areas of fog in the morning. Mostly cloudy. Highs in the upper 60s. Southeast winds 5 to 10 mph. .SATURDAY NIGHT...Cloudy. A slight chance of rain after midnight. Not as cool. Near steady temperature in the lower 60s. South winds 5 to 10 mph with gusts up to 20 mph. Chance of rain 20 percent. .SUNDAY...Cloudy with a slight chance of thunderstorms. A chance of rain in the morning, then rain in the afternoon. Highs in the lower 70s. Temperature falling into the lower 60s in the afternoon. Southwest winds 10 to 15 mph with gusts up to 30 mph. Chance of rain 80 percent. .SUNDAY NIGHT...Mostly cloudy with a chance of rain in the evening, then partly cloudy after midnight. Much cooler. Less humid with lows around 17. Northwest winds 15 to 20 mph with gusts up to 35 mph. Chance of rain 50 percent. Wind chill values as low as 2 above after midnight. .MONDAY AND MONDAY NIGHT...Mostly clear. Highs in the upper 20s. Lows 15 to 20. Wind chill values as low as zero. .TUESDAY...Sunny. Not as cool with highs in the upper 30s. .TUESDAY NIGHT...Mostly clear in the evening, then becoming partly cloudy. Not as cool with lows in the mid 20s. .WEDNESDAY...Partly sunny. Highs in the mid 40s. .WEDNESDAY NIGHT THROUGH FRIDAY...Partly cloudy. Lows 15 to 20. Highs in the lower 30s. $$