National Weather Service United States Department of Commerce

Dangerous, Record-Breaking Heat to Continue in the Central and Eastern U.S.; Severe Thunderstorms in the Upper Midwest; Critical Fire Weather in the Four Corners

Dangerous, record-breaking heat will continue across most of the central and eastern U.S this week. Heat indices will exceed 100 degrees. Severe storms will be possible from the northern Plains into the Midwest and Great Lakes regions, as well as across the southern Appalachians Thursday, with the primary threat large to very large hail. Critical fire weather to continue in the Four Corners Region 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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(F)

Celsius
(C)

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

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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i.e. Fresno Air Terminal = 333
The Station Pressure in inches is:
The Station Pressure in millibars is:
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