vate sector to help them expand to specific markets, cover the diurnal cycle, and provide information to cities not covered by the NWS. While some private sector companies did not agree that the NWS should issue any UV index, all parties did agree to work towards a standardized UV index scale.

After providing the UV index for several years with a consistently high degree of validation, (Long et al., Bulletin of the American Meteorological Society, 1996), in the summer of 1999, the EPA, the CDC, the American Academy of Dermatologists, the American Cancer Society, and members of Congress asked the NWS to expand its coverage beyond the original 58 cities to 160 cities. The EPA, NWS, private sector and medical community representatives met to consider ways to improve coverage. NWS rejected the EPA’s suggestion that NWS provide UV indices for 160 cities. The NWS decided:

  1. To continue to produce the daily UV index at the original 58 cities;

  2. To deliver over the Internet in gridded format the data necessary for the private sector to create UV indices over the entire U.S., and;

  3. Not to produce a contoured map graphic of UV on NWS Web pages.

The NWS has and continues to have good working relationships with most companies within the commercial weather industry and television broadcasters concerning the UV index product. All generally understand the limitations of any one sector’s service, as well as the expanded possibilities for the private broadcasting and commercial meteorology sectors to communicate the UV index and attendant health messages to the public. By continuing to improve the UV index forecast, and by making the numerical output available to the private sector in gridded format for creation of graphical products, the NWS satisfies both its public health and its economic enhancement missions.

2. For many decades, the National Weather Service has utilized an index called Wind Chill to attempt to describe the effect of temperature on humans during windy conditions. It has been known the Wind Chill formula is flawed and significantly overstates cold, yet the NWS has continued to use it for these many decades and publish and distribute charts to the media, emergency managers and the public, which allow one to plot temperature and wind speed and calculate Wind Chill. Based on this formula, the NWS also issues wind chill advisories.

As a result, it can be argued that schools, businesses and other routine daily operations have, on many occasions, been prematurely curtailed while the NWS knew that the overstatement of values was costing the economy millions.



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