National Weather Service United States Department of Commerce

Severe Thunderstorms and Heavy Rain in the Mississippi Valley; Fire Weather Concerns in the Southern High Plains

Severe thunderstorms and the threat for excessive rainfall will move into the mid-Mississippi and lower Ohio Valleys today. There is potential for a few strong tornadoes, damaging wind gusts, large hail, and scattered flash flooding. Low humidity and windy conditions will continue to produce elevated to critical fire weather conditions across the southern High Plains into midweek. 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

Enter a speed into any blank to convert to all other wind speeds.

 mph    knots       m/sec      km/hr  

Wind Chill Calculation

Enter the temperature in degrees Fahrenheit and wind speed in mph, then click on the Calculate WC to compute the windchill index.
Temp
(F)

Wind
(mph)

Index 

Relative Humidity Calculation

Enter the air temperature and the dew point in degrees Fahrenheit, then click on the Calculate RH to compute the relative humidity.
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: