UV Index Today in Charleston, South Carolina
Charleston's UV Climate
Charleston's historic peninsula and surrounding sea islands — Sullivan's, Isle of Palms, Folly Beach — sit at a low coastal latitude where the sun turns fierce by mid-spring. The city's walking culture is part of the exposure story: visitors spend hours on foot along the Battery and King Street with limited shade, while the beach communities add sand and water reflection. The famous Lowcountry humidity produces hazy skies that feel protective but barely dent the UV.
Average Annual UV Index
7.5
Peak UV Season
April - September
Sunny Days per Year
209
Typical UV Index by Season in Charleston
| Season | Typical Midday UV | Protection Needed |
|---|---|---|
| Summer | Very High (9-10) | SPF 30+, hat, sunglasses; shade from 10 AM – 4 PM |
| Spring & Fall | Moderate to High (5-8) | SPF 30+ for extended time outdoors |
| Winter | Low to Moderate (2-4) | Sunscreen for long midday exposure; more on snow |
UV Index in Nearby Cities
- UV Index in Myrtle Beach, SC87 mi away
- UV Index in Wilmington, NC152 mi away
- UV Index in Charlotte, NC177 mi away
- UV Index in Jacksonville, FL197 mi away
Practical Tips for Outdoor Activities
Make the most of outdoor activities while staying safe in Charleston County:
- Check UV index and weather radar before planning outdoor activities
- Schedule outdoor activities during low UV hours
- Use appropriate sun protection based on UV levels
- Stay hydrated during outdoor activities
- Take regular breaks in shaded areas
- Monitor weather conditions for changes
- Be prepared for sudden weather changes
- Know the signs of heat-related illness
- Wear a hat and protective clothing
- Check visibility conditions before outdoor plans
- Stay alert to weather alerts and warnings
UV and Weather in Charleston County
Learn about Charleston County's unique climate patterns, UV radiation levels, and how they affect your daily life. Enter your zip code for location-specific weather radar data and UV forecasts to help you make informed decisions about outdoor activities and sun protection.
Climate and UV Patterns
Charleston's humid subtropical climate brings very high summer UV, with midday index values of 9-10 from May through August and a high-UV season stretching April into September. The maritime haze scatters visible light — that soft Lowcountry glow — while transmitting most UV, a combination that produces burns on days that never looked harsh. Winters are mild, keeping moderate midday UV in play for golf and harbor days.
UV Index and Health Impact
Understanding UV radiation levels is crucial for protecting your health. Typical clear-day UV index values in Charleston through the year:
- Summer: Very High (9-10)
- Spring/Fall: Moderate to High (5-8)
- Winter: Low to Moderate (2-4)
- Peak UV hours: 10 AM - 4 PM
- Cloud cover can reduce UV by 20-40%, but does not eliminate it
- Clear skies bring maximum UV exposure
Local Weather Patterns
Summer follows the sea-breeze script: steamy sunny mornings, then afternoon thunderstorms that fire inland and sometimes drift back over the peninsula after peak hours. Hurricane season occasionally interrupts with extended cloud, but most late-summer days open bright. Winter is Charleston's understated gem — mild, often brilliantly clear days where tourists walk for hours under a moderate midday sun they never think about.
Frequently Asked Questions About UV in Charleston
What is the UV index in Charleston today?
The live UV index for Charleston, SC is shown at the top of this page and updates throughout the day, along with today's maximum and an hourly forecast.
When is the sun strongest in Charleston?
UV radiation is strongest between 10 AM and 4 PM. Charleston's peak UV season runs April - September, when the midday index typically reaches Very High (9-10).
How high does the UV index get in Charleston?
Summer days in Charleston typically reach Very High (9-10). Spring and fall usually bring Moderate to High (5-8), while winter values are typically Low to Moderate (2-4).
Do I need sunscreen in Charleston during winter?
Yes for long outdoor days — Charleston's clear winter afternoons reach moderate UV, and all-day walking tours add up more exposure than people expect.
How sunny is Charleston compared to other cities?
Charleston averages about 209 sunny days per year with an average annual UV index around 7.5.