National Weather Service Forecast for: Bay St. Louis MS
Issued by: National Weather Service New Orleans/Baton Rouge, LA
Updated: 1:57 pm CDT Jul 28, 2026
 
Tonight

Tonight: Mostly clear, with a low around 81. West wind around 10 mph.
Mostly Clear

 Wednesday

Wednesday: Mostly sunny and hot, with a high near 95. Heat index values as high as 110. West wind around 10 mph becoming southwest in the afternoon.
Hot

 Wednesday
Night
Wednesday Night: A slight chance of showers and thunderstorms before 2am, then a slight chance of showers and thunderstorms after 4am. Partly cloudy, with a low around 81. Southwest wind around 10 mph. Chance of precipitation is 20%.
Mostly Cloudy
then Slight
Chance
T-storms
 Thursday

Thursday: Showers and thunderstorms likely, mainly after 1pm. Partly sunny, with a high near 90. Heat index values as high as 105. West wind around 10 mph. Chance of precipitation is 60%.
Chance
T-storms then
T-storms
Likely
 Thursday
Night
Thursday Night: A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 79. West wind 5 to 10 mph.
Chance
T-storms

 Friday

Friday: Showers and thunderstorms likely, mainly after 1pm. Partly sunny, with a high near 90. West wind around 10 mph. Chance of precipitation is 70%.
Chance
T-storms then
T-storms
Likely
 Friday
Night
Friday Night: A 30 percent chance of showers and thunderstorms, mainly before 1am. Mostly cloudy, with a low around 78. West wind 10 to 15 mph.
Chance
T-storms

 Saturday

Saturday: Showers likely and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 87. West wind 10 to 15 mph. Chance of precipitation is 60%.
Showers
Likely

 Saturday
Night
Saturday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 77. Southwest wind around 15 mph.
Chance
T-storms then
Showers
Likely
Lo 81 °F Hi 95 °F Lo 81 °F Hi 90 °F Lo 79 °F Hi 90 °F Lo 78 °F Hi 87 °F Lo 77 °F

Extreme Heat Warning
Extreme Heat Warning
 

Tonight
 
 Mostly clear, with a low around 81. West wind around 10 mph.
Wednesday
 
 Mostly sunny and hot, with a high near 95. Heat index values as high as 110. West wind around 10 mph becoming southwest in the afternoon.
Wednesday Night
 
 A slight chance of showers and thunderstorms before 2am, then a slight chance of showers and thunderstorms after 4am. Partly cloudy, with a low around 81. Southwest wind around 10 mph. Chance of precipitation is 20%.
Thursday
 
 Showers and thunderstorms likely, mainly after 1pm. Partly sunny, with a high near 90. Heat index values as high as 105. West wind around 10 mph. Chance of precipitation is 60%.
Thursday Night
 
 A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 79. West wind 5 to 10 mph.
Friday
 
 Showers and thunderstorms likely, mainly after 1pm. Partly sunny, with a high near 90. West wind around 10 mph. Chance of precipitation is 70%.
Friday Night
 
 A 30 percent chance of showers and thunderstorms, mainly before 1am. Mostly cloudy, with a low around 78. West wind 10 to 15 mph.
Saturday
 
 Showers likely and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 87. West wind 10 to 15 mph. Chance of precipitation is 60%.
Saturday Night
 
 A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 77. Southwest wind around 15 mph.
Sunday
 
 Showers likely and possibly a thunderstorm before 1pm, then showers and thunderstorms likely after 1pm. Partly sunny, with a high near 86. West wind around 15 mph.
Sunday Night
 
 A chance of showers and thunderstorms. Partly cloudy, with a low around 77. Southwest wind 10 to 15 mph.
Monday
 
 A chance of showers and thunderstorms. Mostly sunny, with a high near 88. West wind around 10 mph.
Monday Night
 
 A chance of showers and thunderstorms. Partly cloudy, with a low around 78. Southwest wind 5 to 10 mph.
Tuesday
 
 A chance of showers and thunderstorms. Mostly sunny, with a high near 89. South wind 5 to 10 mph.

 

Forecast from NOAA-NWS for Bay St. Louis MS.