World Resorts USA St. Simons Island Weather

St. Simons Island sea water temperature

Current sea water temperature:
+55.4°F
Minimum sea water temperature in December: 67.5°F
Maximum sea water temperature in December: 49.8°F
Average sea water temperature in December: 59.4°F

Sea water temperature for the last 10 days:

December 23 55.4°F December 18 53.4°F
December 22 54.9°F December 17 53.6°F
December 21 54.1°F December 16 56.3°F
December 20 53.1°F December 15 57.4°F
December 19 54.3°F December 14 55.8°F

When is the warmest sea in St. Simons Island?

Based on the data about daily sea water temperature for the last three years the warmest sea in St. Simons Island was noticed in August, July and September.

Monthly Sea Temperatures in St. Simons Island, °F

Sea water temperature in August, °F

Show year:
2025
2024
2023

The average sea water temperature in August of 2025 was 85.7°F. The highest and lowest sea temperatures during the month were 87.6°F and 83.5°F.

Sea water temperature in July, °F

Show year:
2025
2024
2023

The average sea water temperature in July of 2025 was 84.5°F. The highest and lowest sea temperatures during the month were 87.6°F and 81.7°F.

Sea water temperature in September, °F

Show year:
2025
2024
2023

The average sea water temperature in September of 2025 was 80.7°F. The highest and lowest sea temperatures during the month were 83.5°F and 77.9°F.

Best time for vacation in St. Simons Island

Sunniest months:
October 15 days
January 14 days
March 14 days
Warmest months:
July 88.3 °F
August 86.9 °F
June 86.1 °F
Warmest sea temp:
August 85.1 °F
July 84.6 °F
September 82.0 °F
Coldest months:
January 59.8 °F
December 62.7 °F
February 64.8 °F
Rainiest months:
August 5 days
July 5 days
September 4 days
Windiest months:
December 6.7 mph
October 6.7 mph
January 6.7 mph

St. Simons Island on a weather map

St. Simons Island
+55°F
SE 5 mph
Feels like: +55°F
Precip.: 0%
Places in USA:
Name
°F
+37°F
+73°F
+73°F
+59°F
+59°F
+70°F
+75°F
+68°F
+36°F
+61°F
+57°F
+66°F
+64°F
+70°F
+39°F
24 Hours Forecast
St. Simons Island
Local time: 23:13
December 24, wednesday
0000
55°F
SE
5 mph
0300
55°F
E
6 mph
0600
54°F
E
6 mph
0900
55°F
E
6 mph
1200
61°F
SE
6 mph
1500
70°F
SE
4 mph
1800
72°F
NE
1 mph
2100
68°F
NE
3 mph
Units of measurement: °C / °F