National Weather Service Forecast for: Mehlville MO
Issued by: National Weather Service Saint Louis, MO
Updated: 1:20 am CDT Aug 20, 2026
 
Overnight

Overnight: Patchy fog after 4am. Otherwise, partly cloudy, with a low around 70. Calm wind.
Patchy Fog

 Thursday

Thursday: Patchy fog before 8am. Otherwise, partly sunny, with a high near 83. Calm wind becoming north around 6 mph in the afternoon.
Patchy Fog
then Mostly
Sunny
 Thursday
Night
Thursday Night: Patchy fog after 4am. Otherwise, mostly clear, with a low around 67. Light northeast wind.
Mostly Clear
then Patchy
Fog
 Friday

Friday: Patchy fog before 8am. Otherwise, sunny, with a high near 87. Calm wind.
Patchy Fog
then Sunny
 Friday
Night
Friday Night: Mostly clear, with a low around 69. Calm wind.
Mostly Clear

 Saturday

Saturday: Sunny, with a high near 86.
Sunny

 Saturday
Night
Saturday Night: Mostly clear, with a low around 67.
Mostly Clear

 Sunday

Sunday: Mostly sunny, with a high near 84.
Mostly Sunny

 Sunday
Night
Sunday Night: A slight chance of showers and thunderstorms. Mostly cloudy, with a low around 66. Chance of precipitation is 20%.
Slight Chance
T-storms
Lo 70 °F Hi 83 °F Lo 67 °F Hi 87 °F Lo 69 °F Hi 86 °F Lo 67 °F Hi 84 °F Lo 66 °F

 

Overnight
 
 Patchy fog after 4am. Otherwise, partly cloudy, with a low around 70. Calm wind.
Thursday
 
 Patchy fog before 8am. Otherwise, partly sunny, with a high near 83. Calm wind becoming north around 6 mph in the afternoon.
Thursday Night
 
 Patchy fog after 4am. Otherwise, mostly clear, with a low around 67. Light northeast wind.
Friday
 
 Patchy fog before 8am. Otherwise, sunny, with a high near 87. Calm wind.
Friday Night
 
 Mostly clear, with a low around 69. Calm wind.
Saturday
 
 Sunny, with a high near 86.
Saturday Night
 
 Mostly clear, with a low around 67.
Sunday
 
 Mostly sunny, with a high near 84.
Sunday Night
 
 A slight chance of showers and thunderstorms. Mostly cloudy, with a low around 66. Chance of precipitation is 20%.
Monday
 
 A 20 percent chance of showers before 1pm. Mostly sunny, with a high near 84.
Monday Night
 
 A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 68.
Tuesday
 
 A 20 percent chance of showers. Mostly sunny, with a high near 88.
Tuesday Night
 
 Partly cloudy, with a low around 70.
Wednesday
 
 Mostly sunny, with a high near 89.

 

Forecast from NOAA-NWS for Mehlville MO.