UV Index in Stanford, United States

Last updated: July 2, 2025

Understanding the UV Index in Stanford, United States is crucial for protecting your skin and overall health. With the region's Cfa climate, residents face varying UV exposure risks throughout the day, particularly peaking around midday when levels can soar to 11—indicating a very high risk of harm from unprotected sun exposure. By keeping an eye on the UV Index, you can take essential measures to prevent sunburn and long-term skin damage, ensuring you enjoy the beautiful California sunshine safely. Stay informed and embrace the outdoors responsibly!

Hourly UV Index in Stanford

The UV Index for the day reflects a dynamic shift in solar intensity as the hours progress. Starting off at a mild 1 at 07:00, the index gradually climbs, hitting 2 by 09:00. A noticeable surge occurs between 10:00 and 12:00, where it peaks at an impressive 9. The hottest moments arrive at 13:00 and 14:00, reaching a maximum of 11, indicating a high risk for sun exposure. As the afternoon wanes, the UV levels gently decline, dropping to 5 by 17:00 and further down to 1 by 19:00. Be sure to take precautions during the midday hours to protect your skin from potential harm!

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	1	low	45 min
09:00	2	low	45 min
10:00	4	moderate	30 min
11:00	7	high	25 min
12:00	9	very high	15 min
13:00	10	very high	15 min
14:00	11	extreme	10 min
15:00	9	very high	15 min
16:00	7	high	25 min
17:00	5	moderate	30 min
18:00	3	moderate	30 min
19:00	1	low	45 min

Monthly UV Index Trends in Stanford

Throughout the year, the UV Index experiences significant fluctuations, indicating varying levels of sun exposure risk. The high-risk months for UV exposure are primarily from April to August, where indices peak at 11 in June and July, categorized as extreme with a burn time of only 10 minutes. It is crucial for both visitors and residents to take precautions during this period, such as wearing protective clothing and applying sunscreen frequently. As spring transitions into summer, the UV index rises sharply, reaching very high levels in May and August, and dropping to high in March and October. The months of January, November, and December see lower risks with a moderate index of 3 or 5, allowing for more extended safe sun exposure times of 30 minutes. Visitors and residents should monitor UV levels closely and adjust outdoor activities accordingly to safeguard their skin health.

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	6	7	9	10	11	11	10	9	7	5	3
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