National Weather Service United States Department of Commerce

Severe Thunderstorms in the Ohio Valley and Mid-Atlantic; Heat Continuing in the Central U.S.

Widespread strong to severe thunderstorms are expected from the Upper Ohio Valley into the Mid-Atlantic through Friday, with damaging winds as the primary threat. Dangerous heat will continue from the South-Central U.S. to the Midwest, Ohio/Tennessee valleys, and Mid-Atlantic. Widespread Major to Extreme Heat Risk is forecast into the weekend and will confine to the South-Central U.S. by Labor Day Read More >

National Weather Service Hanford, CA
Meteorological Calculator
Thanks to Ron Murphy, NWS Birmingham, AL for writing the JavaScript.

Temperature Conversion

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Wind Speed Calculations

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 mph    knots       m/sec      km/hr  

Wind Chill Calculation

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Wind
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Index 

Relative Humidity Calculation

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Dew
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Heat Index Calculations

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RH

HI 

Tdp

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Tdp

HI  RH 

Station Pressure Calculation

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