Saint Simons Island

Planning your day on St. Simons Island? Here you will find the most up-to-date weather information, including detailed forecasts and useful charts, to ensure your stay is as comfortable as possible.

The climate on St. Simons Island can be described as humid subtropical. This means you can expect mild winters and hot, humid summers. Moderate temperature fluctuations occur throughout the year, making it an attractive destination across different seasons, though the specific characteristics of each should be considered.

St. Simons Island has clearly defined seasons. Summer, especially from June to August, features high temperatures averaging 27-28°C, with peaks sometimes exceeding 30°C. This period also has the highest number of rainy days, indicating high humidity and frequent, though not always heavy, rain. Winters, by contrast, are quite mild, with average temperatures around 12-15°C, and frost is rare. Spring and autumn are comfortable transitional periods with pleasant, warm weather.

One notable feature of the weather on St. Simons Island is the significant increase in rainy days during the summer months (June, July, August), when they can reach 18-23 days per month. However, the total precipitation remains relatively low, suggesting frequent short-lived showers or high humidity rather than prolonged rainfall. In other months, the number of rainy days is significantly lower, averaging 8-11 days.

St. Simons Island sees distinct temperature shifts throughout the year, offering diverse conditions for visitors. The coldest month is traditionally January, with an average temperature of 12.7°C. During this period, average lows drop to 8.7°C, while average highs can reach 16.7°C. Conversely, the peak heat occurs in the summer months, particularly July, when the average air temperature is 28.0°C, and daytime highs regularly climb to 31.2°C. August is also very warm, with an average temperature of 27.8°C and highs around 30.7°C.

The summer season on St. Simons Island, spanning from June to August, is characterized as hot and quite humid. Average daytime temperatures consistently exceed 27°C, often reaching and surpassing the 30°C mark. Nights during this time also remain warm, with lows typically in the 23-25°C range. The winter months, from December to February, are mild and cool. Average temperatures during this period range from 12.7°C in January to 15.7°C in February. Nighttime temperatures rarely drop to critically low levels, averaging above 8°C, while daytime air can warm up to a comfortable 16-19°C.

The spring months (March-May) bring gradual warming: the average temperature rises from 17.7°C in March to 24.2°C in May. In autumn (September-November), the opposite trend occurs—the temperature gradually decreases from a hot 26.1°C in September to a more moderate 17.6°C in November. Temperature fluctuations between daytime highs and nighttime lows throughout the year on St. Simons Island are moderate, usually showing a difference of 6-8°C. This means that while the difference between daytime heat and nighttime cool is noticeable, sharp daily temperature drops are generally not observed.

St. Simons Island experiences distinct seasonality in its precipitation patterns. The highest number of rainy days and total rainfall occurs during the summer months, from June to September, indicating a wetter season at this time of year. Winter, spring, and mid-autumn are generally characterized by less rainfall and fewer rainy days. Given the island's mild climate, precipitation here falls primarily as rain.

Humidity peaks in August, which sees the highest rainfall (averaging 6 mm) and the maximum number of rainy days—around 23. July is also a rainy month with 5 mm of precipitation and approximately 22 rainy days. June and September also contribute to the wet season with 4 mm and 5 mm of rainfall and 18 and 16 rainy days, respectively. It is important to note that even in the wettest months, total precipitation remains moderate, suggesting frequent but likely not too intense or prolonged showers.

The driest months by total volume are January, April, May, and October, each averaging just 2 mm of rainfall. In terms of rainy days, the lowest values are observed in January, March, and April (around 8 days). During these periods, rain occurs less frequently and is usually brief, providing more sunny days for relaxation and exploring.

When planning a trip to St. Simons Island, it's important to consider its mild climate with pronounced humidity and frequent, though light, precipitation throughout the year. In summer, from June to August, it is quite hot and humid, with average temperatures hovering around 27-28°C. Be sure to pack light, breathable clothing: t-shirts, shorts, sundresses, and, of course, swimwear. Given that there can be up to 23 rainy days in the summer months, a compact umbrella or a light raincoat will be very useful. Don't forget sunscreen, a hat, and sunglasses, as the sun is quite strong here.

During the cooler months, from December to February, the average temperature stays around 12-15°C. For this period, jeans or trousers, sweaters, fleeces, and a light jacket are suitable. Spring (March-May) and autumn (September-November) offer very comfortable but sometimes changeable weather. Layering is the perfect strategy here: t-shirts and long-sleeved shirts that can be topped with a light jacket or cardigan. Regardless of the time of year, comfortable shoes for walking around the island are an absolute necessity. Since even the drier months have 8-10 rainy days, a small umbrella will come in handy any time of year.