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As of September 1, 2014, the NOAAWatch website will be discontinued. Active weather alerts will continue to be available 24/7 at Hurricane tracking widgets will continue to be available at and Learn about ways to get updates through social media at For information about how to reach other NOAA data and information, please email A temporary redirect of website traffic to NOAA’s homepage will exist for a short period of time after the shut-down of

UPDATE:  The NWS has replicated the NOAAWatch Briefing Page which can be found at

UV rays
Ultraviolet (UV) Radiation - A Silent Hazard

The sun emits energy over a broad spectrum of wavelengths: visible light that you see, infrared radiation that you feel as heat, and ultraviolet (UV) radiation that you can't see or feel. UV radiation has a shorter wavelength and higher energy than visible light. It affects human health, both positively and negatively. Short exposure to UV radiation generates vitamin D, but can also lead to sunburn.

Fortunately for life on Earth, our atmosphere's ozone layer shields us from most of the dangerous UV radiation wavelengths. However, what does get through the ozone layer can still cause serious health problems. Since the benefits of sunlight cannot be separated from its damaging effects, it is important to understand the risks of overexposure and take simple precautions to protect yourself.

Health effects of overexposure include:
Skin cancer (melanoma and nonmelanoma)
Premature aging of the skin and other skin problems
Cataracts and other eye damage
Immune system suppression

More information about the health effects of UV radiation can be found at

The UV Index

UV Index forecast

NOAA's National Weather Service (NWS) and the Environmental Protection Agency (EPA) helped develop the internationally accepted standards for the UV Index and best practices to avoid overexposure to solar UV radiation.

The UV Index predicts the next day's mid-day's solar radiation levels on a 0 to 11+ scale, with 11+ signifying an extreme risk of overexposure to the sun's UV rays, while a 1 signifies very low risk. The forecast is determined by the NWS for thousands of points across the United States. To find out what the UV Index forecast is for your local area go to: and click the Mobile Web link.

For more information about UV radiation and the UV Index go to:


The EPA and NWS are using social media to promote the UV Index as a public health tool. The UV Index is available as a smart phone app for iPhone, Android, and BlackBerry phones, a widget, and a desktop gadget. These agencies work with the media and the tourism industry to encourage the publication of UV Index forecasts and promote sun protection messages. To download the smart phone app go to:

The National Weather Service's UV Alert

The UV Alert system issues a notification when the level of solar UV radiation is forecasted to be unusually high for a given location and time of year. The UV Alert is broadcast through the free EnviroFlash Service. Sign up at: UV .

Safety Tips

Follow these steps to help you and your family be "SunWise":
Do not burn
Avoid sun tanning and tanning beds
Use sunscreen
Cover up
Seek shade
Watch for the UV Index
Use extra caution near water, snow, and sand

Sun Safety Awareness Campaigns

Don't Fry Day

The EPA, NWS, the Occupational Safety and Health Administration (OSHA), the Food and Drug Administration (FDA), and the Centers for Disease Control and Prevention (CDC) join with the National Council on Skin Cancer Prevention for Don't Fry Day, a national day of sun safety awareness on the Friday before Memorial Day.

A Focus on Youth

In response to the serious public health threat posed by overexposure to UV rays, the EPA developed the SunWise program. This program is a national environmental and health education program that teaches children and their caregivers how to be safe in the sun through the use of classroom-, school-, and community-based components.

SunWise schools and partners both teach and practice sun-safe behaviors. With the free SunWise toolkit, educators help raise sun safety awareness by addressing the science of the sun, the risk of overexposure to UV radiation, and what children and their families can do to protect themselves from overexposure.

The EPA partners with the SHADE Foundation on SunWise with a SHADE Poster Contest for grades K-8 that receives over 10,000 entries yearly. Through participating in this fun contest, children learn sun safe behaviors.

For more information on these programs, how to get involved, and to obtain free educational resources, please visit: .

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UV Index

Ultraviolet (UV) Radiation


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