San Diego Heat Index Today
Updated planning preview · 4:00 PM forecast from WeatherAPI
Heat index
85°F
Moderate
Use normal heat precautions and take breaks.
Temperature
82°F
Humidity
67%
Estimated WBGT
26.0°C
UV index
3.9
Best outdoor window
6:00 PM–9:00 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 |
|---|---|---|---|---|---|
| 4 PM | 82°F | 85°F | 26.0°C | 3.9 | Moderate |
| 6 PM | 78°F | 81°F | 24.6°C | 0.5 | Moderate |
| 7 AM | 71°F | 76°F | 22.0°C | 0.2 | Low |
| 9 AM | 73°F | 77°F | 22.5°C | 2.6 | Low |
| 11 AM | 76°F | 79°F | 23.2°C | 7.6 | Low |
| 1 PM | 76°F | 79°F | 23.1°C | 9.7 | Low |
| 3 PM | 75°F | 78°F | 22.9°C | 6.6 | Low |
| 5 PM | 75°F | 78°F | 22.5°C | 1.9 | Low |
Today's outlook
In San Diego, the highest modeled heat burden in this preview occurs around 6:00 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 95°F
87° / 68°
HighFriday
Heat index up to 79°F
76° / 68°
LowSaturday
Heat index up to 80°F
78° / 72°
LowToday in San Diego
What changes across the day
Based on the available hourly WeatherAPI forecast
Peak heat index
85°F at 4:00 PM
The preview low is 76°F around 7:00 AM.
Feels-like difference
4°F above air temp
Current humidity is 67%, one input that changes evaporative cooling.
Peak UV
9.7 at 1:00 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 68–87°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.
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