UV Index in Grayson, United States

Last updated: June 2, 2025

Understanding the UV Index is crucial for residents of Grayson, United States, where sunny days can lead to significant sun exposure. With UV levels soaring from 1 in the morning to a peak of 11 during midday, awareness is key in preventing sunburn and protecting skin health. Grayson’s humid subtropical climate, characterized by hot summers, heightens the risk of UV exposure, making it essential for everyone to stay informed and take necessary precautions when heading outdoors. Whether you're basking in the sun or enjoying outdoor activities, knowing the UV Index can help safeguard your skin and keep you safe under the sun.

Hourly UV Index in Grayson

The UV Index for the day reveals a dynamic shift in sun exposure, starting off low in the early morning hours with values of 1 at both 7:00 and 8:00. As the sun climbs higher, the index ramps up, peaking at an intense 11 between 13:00 and 14:00—a clear signal for sun safety measures. This period of maximum intensity comes after a sharp rise from 3 at 9:00 to a notable 7 at 11:00. The afternoon provides a gradual decline, with levels falling to 9 by 15:00, then tapering off to 3 by 18:00 before returning to a safe 1 at 19:00. It's a solid reminder to 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	1	low	45 min
09:00	3	moderate	30 min
10:00	5	moderate	30 min
11:00	7	high	25 min
12:00	10	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 Grayson

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 Grayson, United States

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

The table above highlights how UV exposure in Grayson 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.

Grayson'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
Grayson	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