National Weather Services Duties Act of 2005
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(d) PROHIBITION ON CERTAIN DISCLOSURES- An officer, employee, or agent of the National Oceanic and Atmospheric Administration, the National Weather Service, or any other department or agency of the United States who by reason of that status comes into
possession of any weather data, information, guidance, forecast, or warning that might influence or affect the market value of any product, service, commodity, tradable, or business may not--
(1) willfully impart, whether directly or indirectly, such weather data, information, guidance, forecast, or warning, or any part thereof, before the issuance of such weather data, information, guidance, forecast, or warning to the public under subsection (c); or
(2) after the issuance of such weather data, information, guidance, forecast, or warning to the public under subsection (c), willfully impart comments or qualifications on such weather data, information, guidance, forecast, or warning, or any part thereof, to the public, except pursuant to an issuance that complies with that subsection.
From Thomas:
http://thomas.loc.gov/cgi-bin/query/D?c109:3:./temp/~c109yrBBqj::It's interesting to note that Accuweather is based in PA and is a major Tricky Rick contributor.