Charleston Heat Index Today
Updated planning preview · 7:00 PM forecast from WeatherAPI
Heat index
105°F
Very high
Reschedule strenuous activity when possible.
Temperature
91°F
Humidity
66%
Estimated WBGT
30.6°C
UV index
0.3
Best outdoor window
4:00 PM–7:00 AM
Lowest combined heat and UV load in the available hourly preview.
Hourly heat risk
WBGT values are labeled as modeled estimates until a provider supplies measured readings.
| Time | Temperature | Heat index | Estimated WBGT | UV | Risk |
|---|---|---|---|---|---|
| 7 PM | 91°F | 105°F | 30.6°C | 0.3 | Very high |
| 8 AM | 81°F | 86°F | 26.5°C | 0.5 | Moderate |
| 10 AM | 88°F | 95°F | 28.4°C | 3.4 | High |
| 12 PM | 92°F | 100°F | 29.4°C | 7.2 | High |
| 2 PM | 93°F | 100°F | 29.5°C | 8.9 | High |
| 4 PM | 92°F | 98°F | 29.0°C | 5.1 | High |
| 6 PM | 88°F | 94°F | 28.1°C | 1.1 | High |
| 7 AM | 74°F | 79°F | 24.8°C | 0.0 | Low |
Today's outlook
In Charleston, the highest modeled heat burden in this preview occurs around 7:00 PM. The recommended window is selected from the lowest combined risk score, temperature, and UV—not from generic city copy.
Three-day forecast
Thursday
Heat index up to 116°F
96° / 84°
Very highFriday
Heat index up to 100°F
93° / 76°
HighSaturday
Heat index up to 100°F
93° / 74°
HighToday in Charleston
What changes across the day
Based on the available hourly WeatherAPI forecast
Peak heat index
105°F at 7:00 PM
The preview low is 79°F around 7:00 AM.
Feels-like difference
14°F above air temp
Current humidity is 66%, one input that changes evaporative cooling.
Peak UV
8.9 at 2:00 PM
UV and heat are separate hazards; the lowest-heat hour may still need sun protection.
Tomorrow's direction
16°F cooler tomorrow
Today's forecast range is 84–96°F.
Where these numbers come from
WeatherAPI supplies the forecast. HeatGuard calculates heat-index risk and models WBGT from forecast temperature, humidity and a daytime solar allowance. Modeled WBGT is not an on-site globe-thermometer reading.
Keep planning
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