Charleston weather by month

Regulars are specific this counts among the most unpredictable months of the year here, alongside January and early March, a trip landing anywhere from the upper 60s Fahrenheit down to the low 40s depending purely on which weather pattern happens to be passing through. Our row backs that mild, genuinely wet read, 17.5C over 10C nights feeling 7C, with 60mm of rain across 6 days and a real 20.4 kph wind. Regulars are consistent mostly sunshine remains the more common outcome despite the real cold-snap risk, a coat and scarf, maybe gloves, covering most of what's actually needed to stay comfortable. The sea sits at a cold 14.9C. The record: 7.7 hours of sun, humidity 77 percent and AQI 41.

March in Charleston is the month regulars call variable before they call it good: some years it is in the upper 60s and low 70s F by the middle of the month, others it stays cold and wet throughout. What makes the gamble worth taking is the azaleas, which come out mid to late March and peak from the end of the month through the first two or three weeks of April - White Point Gardens and Hampton Park are the names they give. Two warnings travel with it. The garden festival pulls people from well outside the city, so downtown is busier than the tourist calendar suggests, and the tree pollen through March and early April gets described as sand-thick, the price of all the greenery. The record: 19.7C days, 12.7C nights, 5.7 precipitation days carrying 75.2mm, 9.1 hours of sun and a 21 kph wind.

Charleston's forum calls April excellent, generally mid-to-upper 70s°F with humidity still relatively low, flowers in bloom, and rarely dipping into uncomfortably cool territory. Regulars flag early April sand gnats as a real nuisance for bare ankles and legs, and note the ocean itself stays cool by local standards until a run of full sun warms it up.

Charleston-forum threads on early May weather call it largely comfortable, temperatures in the 70s and 80s Fahrenheit, though posters are honest that humidity can turn oppressive on some days even this early in the season. Mid-to-late May is where it noticeably tips over into genuinely warm and humid, ahead of the full summer swelter still to come. Downtown is also at its busiest in May, one of the year's three peak months alongside April and October, so crowds compound the heat rather than easing it. The record: 29.3C days feeling like a sticky 33C, 23.8C nights, 132mm across 8.4 days, a 25.7C sea, 80 percent humidity and 11.3 hours of sun - warmer and more humid than the largely-comfortable framing suggests by month's end.

Charleston-forum threads on July weather don't dress it up: temperatures regularly near 90F degrees on the thermometer, but the heat index pushes into triple digits most afternoons, and posters specifically flag downtown's brick and pavement as radiating extra heat back at pedestrians on top of the base forecast. Pop-up afternoon thunderstorms are described as a near-daily feature, arriving fast and hard enough that one side of a street can be pouring while the other stays completely dry - an umbrella is called essential rather than optional. Regulars are split on whether it's worth it: many say the heat and humidity are the only downside and everything indoors runs cold, while others recommend simply waiting for October instead. Early morning is the consistent window regulars suggest for outdoor sightseeing. The record: a scorching 31.3C by day feeling like a punishing 37C, 25.6C nights, 149mm across 11.4 days, 82 percent humidity, a 30.3C sea and 11.4 hours of sun.

Forum posters describe October as fabulous - warm, sunny days without summer's stifling humidity, with evenings cool enough for a light jacket or sweater but never so cold it limits activities. Posters citing specific years report highs commonly in the 70s-80sF with an average around 75F, though conditions do genuinely vary: one October saw mostly clear days, while a different year's back half brought more cloud and rain than typical. Posters consistently note October runs statistically a bit drier than September, since September carries the greater tropical-storm risk. The clear tradeoff for the good weather: posters describe October as noticeably more crowded than November, so anyone prioritizing quieter streets over ideal temperatures might lean toward the following month instead.

November is the month Charleston regulars pick, and several call it their favourite: this is one of the two peak seasons here, spring being the other, because summer is the part locals escape. The weather they describe is good but genuinely unpredictable - it can be above 70F or it can be in the 40s and 50s, with highs around 70 typical and the nights dropping through the 60s into the 50s as the month runs. Our row's 19.9C day over a 12.5C night is the middle of that. Their packing answer is layers plus an umbrella, and their specific warning is not to plan on t-shirts alone, because the gap between early morning and mid-afternoon does the work. The record: 5.8 precipitation days carrying 49.2mm, humidity 75 percent and 7.9 hours of sun.