National Weather Service United States Department of Commerce

Heavy Rain in the Southern Appalachians; Heat Continues in the West; Monitoring Tropical Storm Erin

Heavy to excessive rain falling over the southern Appalachians may bring areas of flooding into Wednesday. Hot temperatures are in place through Wednesday across parts of the western U.S. and New England. Tropical Storm Erin is forecast to become a Hurricane by late this week as it moves westward across the central Atlantic Ocean. Monitor forecasts for any Puerto Rico or U.S. East Coast impacts. Read More >

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

Temperature Conversion

Enter a number then click on the the conversion button.
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: