UV Index in Vista, United States

Last updated: May 3, 2025

In Vista, California, staying informed about the UV Index is crucial for protecting your skin from harmful ultraviolet (UV) radiation. Understanding UV levels not only helps you prevent painful sunburns, but also contributes to long-term skin health by reducing the risk of skin cancer. With Vista's Mediterranean climate, characterized by warm, sunny summers, residents face increased exposure to UV radiation, especially during peak hours. By being aware of the UV Index, you can take proactive measures to enjoy the beautiful sun safely!

Hourly UV Index in Vista

The UV Index demonstrates a clear peak in intensity throughout the day, showcasing the need for sun protection during certain hours. Starting from a low of 1 at 07:00, the index rises steadily, reaching 4 by 09:00, before surging to a powerful 11 at midday. This intense level of UV radiation persists until 13:00, emphasizing the risk during these prime hours. As the afternoon progresses, the index gracefully declines, registering 9 at 14:00 and tapering off to a more moderate 3 by 17:00. By evening, it drops back to 1, signaling a safe window for outdoor activities as the sun sets. Be mindful of these fluctuations and stay protected during peak hours!

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

Monthly UV Index Trends in Vista

Throughout the year, UV exposure varies significantly, with the highest UV Index levels observed from March to August. The months of May and June peak at an extreme UV Index of 11 and 12, where the burn time drops to just 10 minutes, posing a significant risk for sunburn. March and April also present substantial risks, classified as very high with an Index of 9 and 10, and a burn time of 15 minutes. As summer wanes into autumn, the UV Index begins to decrease, but September and October still remain at high levels with burn times of 15 to 25 minutes. Therefore, visitors and residents are strongly advised to prioritize sun safety, especially during the high-risk months of March through August by wearing protective clothing, using sunscreen, and seeking shade during peak sun hours.

Monthly Maximum UV Index for Vista, United States

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

The table above highlights how UV exposure in Vista 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.

Vista'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
Los Angeles UVI	4	6	8	9	10	11	11	10	10	7	5	4
Vista	4	6	9	10	11	12	11	10	10	7	5	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5