Converting Units

Converting meteorological units

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It might be useful for you to know the conversion of units commonly used in meteorology for use in the classroom.

Fahrenheit to Celsius

To convert a Fahrenheit temperature reading to Celsius: first deduct 32 and then multiply the value you get by 5/9.

e.g. 59°F = (59-32)x(5/9) = 27×5/9 = 15°C.

Celsius temperature reading to Fahrenheit

To convert a Celsius temperature reading to Fahrenheit: first multiply by 9/5 and then add 32.

e.g. 20°C = (20×9/5)+32 = 36+32 = 68°F.

To convert inches to millimetres

1 inch = 25.4 mm

To convert millimetres to inches

1 mm = 0.03937 inch

To convert wind-speed units:

[kt = knot; m/s = metres per second; kph = kilometres per hour; mph = miles per hour]
1 kt = 0.515 m/s and 1 m/s = 1.94 kt;
1 kt = 1.853 kph, so 1 kph = 0.54 kt;
1 kt = 1.152 mph, so 1 mph = 0.87 kt.