UV Index in Hayward, United States

Last updated: July 2, 2025

In Hayward, United States, staying informed about the UV Index is crucial for maintaining skin health and preventing sunburn. Understanding UV levels not only helps you plan outdoor activities but also safeguards against the long-term effects of sun exposure. With a climate characterized as Csb, Hayward experiences varying UV risks throughout the day, peaking at an Index of 11 around noon. This highlights the importance of UV awareness, especially during the summer months when the sun is at its strongest. By keeping track of these levels, residents can enjoy the beautiful California weather while protecting their skin.

Hourly UV Index in Hayward

As the day unfolds, the UV Index rises steadily, peaking at 11 around 1 PM—a clear signal for sun protection. Starting from a low of just 1 at 7 AM, it escalates through the morning, hitting 8 by 11 AM. At 12 PM, the intensity reaches a significant 10, before slightly diminishing to 9 at 3 PM and tapering off rapidly in the afternoon. As the sun begins to set, the UV levels drop to 4 by 5 PM, finally settling back to 1 by 7 PM. With this clear UV trajectory, staying cautious during the peak hours, especially from 11 AM to 2 PM, is essential for skin safety. Don your sunscreen and enjoy the sun responsibly!

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	11	extreme	10 min
14:00	10	very high	15 min
15:00	9	very high	15 min
16:00	6	high	25 min
17:00	4	moderate	30 min
18:00	2	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Hayward

The UV Index experiences significant seasonal variation, with the highest risks typically occurring from March to August. During this period, the UV Index peaks at 11, indicating an extreme exposure category in June and July, where the burn time is as short as 10 minutes. Conversely, the months of January, November, and December present a lower risk with a moderate UV Index of 3 to 5, allowing for burn times up to 30 minutes. It is crucial for both visitors and residents to monitor the UV Index regularly, especially during the high-risk months, and to take appropriate sun protection measures, such as wearing sunscreen, protective clothing, and seeking shade during peak hours to prevent skin damage.

Monthly Maximum UV Index for Hayward, United States

The monthly maximum UV Index (UVI) represents the highest UV radiation level recorded each month in Hayward. 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 Hayward, 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 Hayward UV Index with Other United States Cities

The table above highlights how UV exposure in Hayward 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.

Hayward'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
Hayward	3	5	8	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