UV Index in Stanford, United States

Last updated: July 2, 2025

Understanding the UV Index in Stanford, United States, is crucial for maintaining skin health and preventing sunburn. As a city characterized by its Dfa climate, Stanford experiences varying UV levels throughout the day, peaking at 10 around noon. With exposure risks heightened during these hours, being aware of the UV Index helps residents and visitors protect themselves from harmful effects of ultraviolet radiation. Stay informed and enjoy the sunny days while safeguarding your skin!

Hourly UV Index in Stanford

The UV Index data unveils a dynamic progression of sun intensity throughout the day. Starting low at 1 at 07:00, the index gradually escalates, reaching maximum levels of 10 between 12:00 and 14:00. This peak signals a critical time for sun protection. As the afternoon wanes, the index tapers off to 8 at 15:00, and then descends further to 3 by 17:00, and 2 by 18:00. Ultimately, the day concludes softly with a return to 1 at 19:00. It's essential to stay vigilant during those peak hours to safeguard your skin while enjoying the sun!

Average solar exposure data for the current time of the year. Actual values may vary and depend on many factors, such as cloud cover, vegetation cover, surface type, etc.
Time	UVI	Category	Time to Burn
07:00	1	low	45 min
08:00	2	low	45 min
09:00	4	moderate	30 min
10:00	6	high	25 min
11:00	8	very high	15 min
12:00	10	very high	15 min
13:00	10	very high	15 min
14:00	10	very high	15 min
15:00	8	very high	15 min
16:00	6	high	25 min
17:00	3	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Stanford

As the seasons change, so do the UV Index levels, significantly affecting sun exposure and burn times throughout the year. From January to February, UV levels remain moderate (3-5), allowing for a 30-minute burn time. However, starting in March, the UV Index rises to 7, indicating high exposure risk with burn times of 25 minutes. The peak risk occurs from April to June, where the UV Index hits 9-11, classifying these months as very high to extreme (with burn times reduced to 10-15 minutes). July and August maintain high levels of sun intensity, but begin to taper off in September (UV Index 8). By October, the UV Index decreases to 6, marking a return to high exposure risk, while November and December offer moderate to low levels (4 and 2 respectively), allowing for longer burn times. Visitors and residents are advised to take extra precautions during high-risk months (March to September) by wearing protective clothing and applying sunscreen regularly, particularly when UV levels are at their peak.

Monthly Maximum UV Index for Stanford, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Stanford. It measures the strength of ultraviolet radiation from the sun and helps assess the risk of sunburn and UV-related health issues.

Data source: Statistical UV Index data for Stanford, based on information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

Compare Stanford UV Index with Other United States Cities

The table above highlights how UV exposure in Stanford compares to other major locations across United States. This comparison helps travelers and residents better understand regional sun intensity and plan outdoor activities with sun safety in mind.

Stanford's solar exposure compared to other cities in United States. Generated using Copernicus Atmosphere Monitoring Service information.
	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Chicago UVI	3	4	6	8	9	10	10	9	8	6	4	2
Brooklyn UVI	3	5	6	8	10	10	9	9	8	6	4	2
New York City UVI	3	5	6	8	10	10	9	9	8	6	4	2
Stanford	3	5	7	9	10	11	10	9	8	6	4	2
Los Angeles UVI	4	6	8	9	10	11	11	10	10	7	5	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5