National Weather Service United States Department of Commerce

Dangerous Heat in the East; Critical Fire Weather in the Southwest

Dangerous, record-breaking heat will intensify across most of the central and eastern U.S this week. Heat indices will likely exceed 100 degrees. Heat is likely to continue across the eastern U.S. through the Independence Day holiday weekend. Critical fire weather conditions will continue today and likely Tuesday across portions of the Four Corners and northern High Plains. 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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Fahrenheit
(F)

Celsius
(C)

Wind Speed Calculations

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 mph    knots       m/sec      km/hr  

Wind Chill Calculation

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Temp
(F)

Wind
(mph)

Index 

Relative Humidity Calculation

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Temp
(F)

Dew
Point

Heat Index Calculations

Enter the temperature in degrees Fahrenheit and relative humidity (RH) in percent (without the % sign), or the Dew Point (Tdp).  Then click on the Calculate HI to compute the heat index (HI).
Temp (F)

RH

HI 

Tdp

OR

Temp (F)

Tdp

HI  RH 

Station Pressure Calculation

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What is the station elevation? (feet)
i.e. Fresno Air Terminal = 333
The Station Pressure in inches is:
The Station Pressure in millibars is:
The Pressure Altitude in feet is: