National Weather Service Forecast for: Bay St. Louis MS
Issued by: National Weather Service New Orleans/Baton Rouge, LA
Updated: 11:31 pm CST Dec 17, 2025
 
Overnight

Overnight: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 3am. Cloudy, with a low around 59. Southeast wind around 10 mph. Chance of precipitation is 70%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Showers
Likely

 Thursday

Thursday: Showers and thunderstorms, mainly before 4pm. Patchy dense fog before 3pm, then patchy dense fog after 5pm. High near 67. Southeast wind around 10 mph becoming south in the afternoon. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Showers and
Patchy Dense
Fog

 Thursday
Night
Thursday Night: A slight chance of showers between 7pm and 9pm. Patchy fog before 11pm. Otherwise, partly cloudy, with a low around 49. South wind 10 to 15 mph becoming north after midnight. Chance of precipitation is 20%.
Slight Chance
Showers and
Patchy Fog
then Mostly
Clear
 Friday

Friday: Sunny, with a high near 60. North wind 5 to 10 mph.
Sunny


 Friday
Night
Friday Night: Clear, with a low around 49. North wind around 5 mph becoming southeast after midnight.
Clear


 Saturday

Saturday: Sunny, with a high near 66. South wind 5 to 10 mph.
Sunny


 Saturday
Night
Saturday Night: Partly cloudy, with a low around 58. South wind 5 to 10 mph.
Partly Cloudy


 Sunday

Sunday: A 20 percent chance of showers after noon. Partly sunny, with a high near 68. Southeast wind 5 to 10 mph.
Partly Sunny
then Slight
Chance
Showers
 Sunday
Night
Sunday Night: A slight chance of showers before midnight. Mostly cloudy, with a low around 56. East wind 5 to 10 mph.
Slight Chance
Showers then
Mostly Cloudy
Lo 59 °F Hi 67 °F Lo 49 °F Hi 60 °F Lo 49 °F Hi 66 °F Lo 58 °F Hi 68 °F Lo 56 °F

Dense Fog Advisory
 

Overnight
 
 A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 3am. Cloudy, with a low around 59. Southeast wind around 10 mph. Chance of precipitation is 70%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Thursday
 
 Showers and thunderstorms, mainly before 4pm. Patchy dense fog before 3pm, then patchy dense fog after 5pm. High near 67. Southeast wind around 10 mph becoming south in the afternoon. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Thursday Night
 
 A slight chance of showers between 7pm and 9pm. Patchy fog before 11pm. Otherwise, partly cloudy, with a low around 49. South wind 10 to 15 mph becoming north after midnight. Chance of precipitation is 20%.
Friday
 
 Sunny, with a high near 60. North wind 5 to 10 mph.
Friday Night
 
 Clear, with a low around 49. North wind around 5 mph becoming southeast after midnight.
Saturday
 
 Sunny, with a high near 66. South wind 5 to 10 mph.
Saturday Night
 
 Partly cloudy, with a low around 58. South wind 5 to 10 mph.
Sunday
 
 A 20 percent chance of showers after noon. Partly sunny, with a high near 68. Southeast wind 5 to 10 mph.
Sunday Night
 
 A slight chance of showers before midnight. Mostly cloudy, with a low around 56. East wind 5 to 10 mph.
Monday
 
 Mostly sunny, with a high near 64. East wind around 10 mph.
Monday Night
 
 Partly cloudy, with a low around 56. East wind 5 to 10 mph.
Tuesday
 
 Sunny, with a high near 67. East wind 5 to 10 mph.
Tuesday Night
 
 Partly cloudy, with a low around 57. East wind around 5 mph.
Wednesday
 
 Mostly sunny, with a high near 67. East wind 5 to 10 mph.

 

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