National Weather Service United States Department of Commerce

Extreme Heat in the Central US Expands to the East; Heavy Rains from the Southern Plains to the Great Lakes

Dangerous, long-lasting heat remains across the Mid-South to Mid-Mississippi Valley, while heat expands into the Northeast for a brief period on Friday. Strong to isolated severe thunderstorms and heavy rain pose a flash flooding threat from from the southern High Plains east to the Great Lakes. Tropical Depression 12W brings heavy rain to Guam & the Marianas through Saturday. Read More >

Weather Calculators

Temperature Conversion

Enter a number then click on the the conversion button.
Fahrenheit
(o F)

Celsius
(o 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
(o 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
(o 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
(o F)

RH

HI

Tdp

OR

Temp
(o F)

Tdp

HI RH