UV Index Today

Real-time solar radiation monitoring

San Francisco, California, United States
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San Francisco

California, United States • Local time: 16:40

Live UV Index
16:00
3.1
Moderate
Peak 4.6 at 14:00

Temp

24.4°C
Cloudy

Status

Cloudy

Max

32.0°C

Next 3 Hours

2.4
17:00
1.1
18:00
0.1
19:00

Humidity

45%

Cloud

100%

Wind Spd

22km/h

"Moderate risk. Seek shade near midday."

Today's UV Forecast

Hourly prediction for San Francisco · Peak 4.6 at 14:00

—
00
—
01
—
02
—
03
—
04
—
05
—
06
—
07
0.1
08
1.0
09
2.1
10
3.6
11
4.5
12
4.4
13
4.6
14
3.3
15
3.1
16
2.4
17
1.1
18
0.1
19
—
20
—
21
—
22
—
23

Sunburn time at UV 3.1

Estimate for San Francisco based on your skin type. Estimates only — not medical advice.

Skin type (Fitzpatrick)

Unprotected

32 min

Type II · no sunscreen

Recommended

SPF 50

Moderate UV with fair skin — use broad-spectrum SPF 50 and seek shade near midday.

With SPF 50

12+ hours

Theoretical window — apply enough and reapply every 2 hours

Quick take: Moderate unprotected window — still use SPF for midday outdoor time.

Open full calculator with SPF options

Location Map

37.7633, -122.4129 · Elev. 18 m · America/Los_Angeles

Open in Google Maps

Today's UV outlook for San Francisco

Today's forecast for San Francisco peaks at UV 4.6 around 14:00. The hourly outlook shows 6 hours at moderate or above (UV 3+). The live reading is UV 3.1 right now.

UV stays mostly in the low-to-moderate range today, but the hourly bars still show when exposure climbs. Fair skin still benefits from SPF for extended time outdoors.

Compare with other cities in California, or read practical planning notes in the blog .