The weather in May in Charleston is always warm and often hot. The average daily high is in the low 80s, frequently reaching into the early 90s on the hottest days. You can expect at least some sun nearly every day this month, with day-long clear skies a common occurence.
The weather is ideal for the beach and for water-based activities, but at the hottest parts of the day, particularly toward the end of the month, you may prefer to escape the heat with an indoor activity or attraction, such as one of Charleston’s many historic houses or museums.
When planning your daily activities, always consult the weather forecast, particularly at the end of the month, when Charleston’s afternoon summer thunderstorms may begin to make an early appearance. Be sure to have a plan for seeking shelter if lightning is predicted.
Pack clothing suitable for warm to hot weather, with an additional layer for cooler days or evenings, plus beach wear and perhaps a bathing suit if you plan on visiting one of the Charleston area’s several beaches or trying out a watersport such as kayaking or paddle boarding.
High-factor sunscreen is a must for all in Charleston and vicinity at this time of year, and you should also pack insect repellent if you will be visiting nature sites. An umbrella is usually a good idea.
See also:
– May festivals and events
– Visiting Charleston in the spring
– 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, June, July, August, September, October, November or December
The daily maximum temperature in Charleston in May averages 83°F (28°C), with the lowest daily highs being around 68-75°F (20-24°C), up to around 90-93°F (32-34°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. The temperature stays below 77°F (25°C) on anywhere between one or two to up to ten days during the month of May.
In the morning, temperatures are around 70-85°F (21-29°C), with evening temperatures generally within a few degrees, either way, of the temperature that morning. Overnight lows are usually in the range of around 50-75°F (10-24°C).
May in Charleston is often very humid, and on some days it can be oppressively so.
Surface water temperature in May at the beaches near Charleston is around 70-76°F (20-26°C), often warm enough for watersports or swimming on hotter days.
May in Charleston averages 9-10 hours of sunshine each day. Rainfall for the month totals an average of 3 inches, with rain occurring on an average of 8 days.
The weather in Charleston in May is often sunny, with a third to a half of days being mostly sunny; as many days again bringing a mix of cloudy and sunny spells (sometimes with a chance of rain); and a few days each month being mostly overcast, again with a possibility of rain.
The average UV index in Charleston in May is 10.
Wind speeds in Charleston in May average around 9mph or so, with 1 or 2 days each month still or mostly still, and 6-8 days on average where wind speeds may reach around 15mph or higher.
In May, the sun rises at around 6:30am at the beginning of the month and at 6:15am at the end of the month. It begins to get light in the morning at 6:05am at the start of the month, and by 5:45am at the end.
The sun sets at around 8pm at the start of the month, and at around 8:20pm by its end. It should be dark by around 8:30 at the beginning of the month, and by 8:50pm at its end.
The amount of full daylight in May averages around 13 hours 50 minutes per day, plus an extra 25-30 minutes of low light at the beginning and end of the day.