National Weather Service United States Department of Commerce

Cold Temperatures Continue in the Central U.S. Today; Pacific Storm to Impact the Pacific Northwest

Persistent arctic air is forecast to break numerous daily records and produce dangerously cold sub-zero wind chills across the Central and Southern Plains, Lower Mississippi Valley, and the Southeast U.S. today. An atmospheric river will bring heavy rain and mountain snow to the Pacific Northwest states and northern Rockies today through at least Tuesday. 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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(F)

Wind
(mph)

Index 

Relative Humidity Calculation

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(F)

Dew
Point

Heat Index Calculations

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Temp (F)

RH

HI 

Tdp

OR

Temp (F)

Tdp

HI  RH 

Station Pressure Calculation

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i.e. Fresno Air Terminal = 333
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