UV Index in Alto, United States

Last updated: July 2, 2025

Understanding the UV Index is crucial for residents and visitors of Alto, United States, where the subtropical Cfa climate brings significant sun exposure year-round. Awareness of UV levels helps in preventing sunburn and protecting skin health, especially during peak hours when the index can reach a striking 11, indicating extreme risk of harm from unprotected sun exposure. With the potential for intense UV radiation, typically peaking around midday, knowing when to seek shade or apply sunscreen becomes vital for maintaining a healthy outdoor lifestyle in this vibrant community.

Hourly UV Index in Alto

The UV Index today presents a dynamic profile, beginning at a calm 1 by 07:00 and remaining low until it reaches 2 by 09:00. The real action starts around 10:00, where the index jumps to 5, setting the stage for peak sunlight. By 12:00, the index soars to a significant 9, creating a strong midday sun that only intensifies, peaking at an impressive 11 between 13:00 and 14:00. As the afternoon progresses, the intensity starts to wane, dipping to 9 at 15:00, then 7 by 16:00, and gradually easing to a gentle 3 as evening approaches. By 19:00, the index falls back to 1, indicating a safe time to enjoy the sunset. Remember to protect your skin during the highest UV exposure 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	1	low	45 min
09:00	2	low	45 min
10:00	5	moderate	30 min
11:00	7	high	25 min
12:00	9	very high	15 min
13:00	11	extreme	10 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 Alto

Throughout the year, UV Index levels exhibit notable seasonal changes. The months of April to July are particularly high-risk, with an extreme UV Index of 11, leading to a burn time of just 10 minutes. This period necessitates extra caution, with visitors and residents advised to wear protective clothing, hats, and sunscreen. As summer wanes, the UV Index gradually decreases but remains very high in August to October, with burn times ranging from 15 to 25 minutes. January and December present the lowest UV levels, categorized as moderate, where burn times extend to 30 minutes. It is essential for everyone to remain vigilant with sun protection, especially during the high-risk months.

Monthly Maximum UV Index for Alto, United States

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

The table above highlights how UV exposure in Alto 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.

Alto'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
Alto	4	7	8	11	11	11	11	10	9	8	6	4
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5