St. Simons, GA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for St. Simons, a community in Glynn County, Georgia.
This Afternoon
92°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms after 3pm. Mostly sunny. High near 92, with temperatures falling to around 85 in the afternoon. Heat index values as high as 103. South wind 8 to 12 mph, with gusts as high as 16 mph. Chance of precipitation is 40%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for St. Simons
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 92°F | Chance Showers And Thunderstorms | 8 to 12 mph S | 41% |
| Tonight | 74°F | Chance Showers And Thunderstorms then Partly Cloudy | 3 to 12 mph S | 51% |
| Wednesday | 92°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 3 to 13 mph S | 19% |
| Wednesday Night | 76°F | Slight Chance Showers And Thunderstorms | 3 to 13 mph S | 33% |
| Thursday | 91°F | Chance Showers And Thunderstorms | 1 to 10 mph S | 33% |
| Thursday Night | 77°F | Slight Chance Showers And Thunderstorms | 5 to 9 mph SE | 19% |
| Friday | 91°F | Chance Showers And Thunderstorms | 5 to 13 mph E | 46% |
| Friday Night | 76°F | Chance Showers And Thunderstorms | 5 to 12 mph E | 39% |
| Saturday | 91°F | Showers And Thunderstorms Likely | 6 to 10 mph SE | 67% |
| Saturday Night | 76°F | Chance Showers And Thunderstorms | 3 to 9 mph S | 35% |
| Sunday | 92°F | Chance Showers And Thunderstorms | 2 to 9 mph S | 36% |
| Sunday Night | 76°F | Chance Showers And Thunderstorms then Partly Cloudy | 3 to 8 mph S | 36% |
| Monday | 94°F | Mostly Sunny then Chance Showers And Thunderstorms | 3 to 9 mph S | 29% |
| Monday Night | 76°F | Chance Showers And Thunderstorms then Partly Cloudy | 5 to 9 mph S | 29% |
Forecast source: National Weather Service (api.weather.gov) for St. Simons (31.180, -81.385). Updated through the day.
Growing snapshot for St. Simons
Last spring frost
Feb 9
First fall frost
Dec 26
Growing season
312 days
Hardiness zone
9a
More local growing data for St. Simons: nearby ZIP 31561 weather · frost dates · planting calendar · Georgia frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Brunswick Malcolm Mckinnon Ap, Ga (6.2 mi from St. Simons). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.