St. Simons Island Weather: September
 |
Average Day Temperature: | 86.5°F |
|
Average Night Temperature: | 76.6°F |
|
Sea Water Temperature: | 85.5°F |
|
Number of Sunny Days: | 9 days |
| Sunshine Hours: | 11.9 - 12.8 hours | |
|
Number of Rainy Days: | 4 days |
| Precipitation Totals: | 1.6 in | |
| detailed information | ||
forecast
| St. Simons Island |
Temperature
| St. Simons Island |
Air Temperature in September, °F
The highest day temperature in September 2025 was 93°F. The lowest night temperature was 73°F. The average values for day and night temperatures during September were 85.8°F и 77.3°F respectivly.
St. Simons Island Water Sea Temperature in September, °F
The average sea surface temperature in September 2025 for St. Simons Island was 84.1°F. The maximum and minimum values were 81.0°F and 87.2°F respectively.
You can expect various weather conditions during September. Be ready for sunny, cloudy or even gloomy days.
Precipitation Totals in September, in
Precipitation total in September for St. Simons Island is 1.6 in. It makes september one of the most rainy months of the year.
The average wind speed in September is 6.5 mph. This value is relatively stable throughout the year.
We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for St. Simons Island in September is 6.6 hours.
St. Simons Island on the Weather Map
| Chicago |  |
0 |
| Hawaii |  |
+78 |
| Honolulu | |
+78 |
| Houston | |
+46 |
| Las Vegas |  |
+44 |
| Los Angeles | |
+56 |
| Maui | |
+72 |
| Miami | |
+72 |
| Miami Beach | |
+80 |
| New York | |
+20 |
| San Diego | |
+58 |
| San Francisco | |
+48 |
| Sarasota | |
+64 |
| Tampa | |
+64 |
| Washington | |
+28 |
| 0300 |  |
58°F | NW 6 mph |
| 0600 | |
60°F | N 6 mph |
| 0900 | |
62°F | NE 4 mph |
| 1200 | |
66°F | NE 5 mph |
| 1500 | |
64°F | NE 4 mph |
| 1800 | |
58°F | S 11 mph |
| 2100 | |
56°F | S 7 mph |
| 0000 |  |
56°F | SE 4 mph |