UV Index in Saint Johns, United States

Last updated: May 3, 2025

Understanding the UV Index is crucial for residents of Saint Johns, United States, where the BSk climate can bring significant sun exposure. Awareness of UV levels helps to prevent sunburn and protect skin health, especially during peak hours when the index reaches its highest values of 12 around midday. With rising UV levels typically peaking between 10:00 AM and 2:00 PM, being informed about these fluctuations can safeguard your wellbeing and encourage safe outdoor activities, allowing you to fully enjoy the sun while minimizing risks.

Hourly UV Index in Saint Johns

At dawn, the UV Index begins modestly, peaking at 2 by 7:00 AM. As the sun climbs, the intensity ramps up, hitting 4 by 8:00 AM and escalating to 6 by 9:00 AM. The sun reaches its zenith around noon, with a significant surge to 12, maintaining this level until 1:00 PM. As the afternoon progresses, the index gradually declines, dropping to 10 by 2:00 PM and continuing to fall to 7 by 3:00 PM. By late afternoon, the UV Index retreats further, settling at 4 by 4:00 PM and then to 2 by 5:00 PM, concluding the day with a gentle 1 at both 6:00 PM and 7:00 PM. Be mindful of peak UV times to protect your skin!

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	2	low	45 min
08:00	4	moderate	30 min
09:00	6	high	25 min
10:00	9	very high	15 min
11:00	12	extreme	10 min
12:00	12	extreme	10 min
13:00	12	extreme	10 min
14:00	10	very high	15 min
15:00	7	high	25 min
16:00	4	moderate	30 min
17:00	2	low	45 min
18:00	1	low	45 min
19:00	1	low	45 min

Monthly UV Index Trends in Saint Johns

Throughout the year, the UV Index shows significant seasonal changes, peaking during the summer months. From January to February, the UV levels rise from moderate (5) to high (7), with burn times decreasing from 30 minutes to 25 minutes. The following months, March through September, present the highest risks, with the UV Index reaching its maximum in June and July at 13, falling within the extreme category where burn times drop to just 10 minutes. After this peak, the index gradually decreases to 8 in October (very high) and continues to decline to 6 in November and 5 in December (both moderate). Visitors and residents are therefore advised to take extra precautions during the high-risk months of March through September, utilizing sunscreen, protective clothing, and seeking shade to mitigate UV exposure.

Monthly Maximum UV Index for Saint Johns, United States

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

The table above highlights how UV exposure in Saint Johns 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.

Saint Johns'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
Houston UVI	5	8	9	11	11	12	12	11	10	9	7	5
Saint Johns	5	7	10	12	12	13	13	12	11	8	6	5