September’s weather in Charleston has much in common with the summer months. Average daily highs are in the mid 80s, and into the 90s on the hottest days, although you can expect more days this month that are slightly cooler and more pleasant than at the height of summer. Humidity remains high through most of the month
September is still a great month for going to the beach, with warm water and smaller crowds after Labor Day. On the hottest days, you will still probably prefer shaded or indoor activities, with more active sightseeing reserved for the mornings. Cooler days, in the 70s or low 80s, should be perfect for outdoor sightseeing, hiking and so on.
Consult the weather forecast before traveling before deciding what to pack, but in general warm- to hot-weather clothing is most appropriate for a September visit to Charleston. You may need an extra layer and maybe a light jacket for cooler mornings and evenings, and for occasional cooler days.
Bring an umbrella for rainy spells, high factor sunscreen, and insect repellent if you will be visiting nature sites.
September is hurricane season in Charleston, with a strong possibility of hurricanes or tropical storms during the month. It is a good idea to take out appropriate insurance if you will be booking travel ahead of time. In the event of dangerous weather during your visit, heed all local advice and be prepared to evacuate if necessary.
See also:
– September festivals and events
– Visiting Charleston in the fall
– When is the best time of year to visit Charleston?
– Things to do during your visit to Charleston
– Charleston's weather by month: January, February, March, April, May, June, July, August, October, November or December
The daily maximum temperature in Charleston in September averages 85°F (29°C), with the lowest daily highs being around 70-75°F (21-24°C), up to around 93°F (34°C) on the hottest days. In an average year, you can expect the temperature to exceed 90°F (32°C) on 5-10 days each month, with a third to a half of days below 85°F (30°C).
In the morning, temperatures are in the range of 65-85°F (18-30°C), with evening temperatures about the same. Night-time lows are typically around 65-75°F (18-24°C).
By September, Charleston’s weather is beginning to feel less humid than during the height of summer, but it will still be extremely humid for much of the month.
Surface water temperature in September at the beaches near Charleston is around 80-83°F (26-29°C), still ideal for swimming and watersports.
The average September in Charleston has 7 or so hours of sunshine each day. Rainfall for the month totals an average of 6.1 inches, with rain occurring on an average of 10 days.
September is generally a fairly sunny month, with around a third of days in the average month being clear, or mostly so, all day. Of the remaining days, at least another third will bring at least some sun, mixed in with cloudier periods. September can also bring quite a few days that are mostly overcast, with a chance of rain.
The average UV index in Charleston in September is 8.
Average wind speeds in Charleston in September are around 8-9mph, with 3-5 days each month with at most only a very light breeze, and 1-3 days on average where wind speeds may reach around 15mph or higher.
In September, the sun rises at around 6:55am at the beginning of the month and at 7:15am at the end of the month. It begins to get light in the morning at 6:30am at the start of the month, and by 6:50am at the end.
The sun sets at around 7:45pm at the start of the month, and at around 7:05pm by its end. It should be dark by around 8:10pm at the beginning of the month, and by 7:30pm at its end.
The amount of full daylight in September averages around 12 hours 20 minutes per day, plus 25 minutes of low light at the beginning and end of the day.