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Subject: A14) How do I convert from mph to knots (or m/s), from inches of mercury to mb (or hPa), or convert degrees of latitude to miles (or kilometers) ? Contributed by Neal Dorst (HRD)

For winds:

1 mile per hour = 0.869 international nautical mile per hour (knot)
1 mile per hour = 1.609 kilometers per hour
1 mile per hour = 0.4470 meter per second
1 knot = 1.852 kilometers per hour
1 knot = 0.5144 meter per second
1 meter per second = 3.6 kilometers per hour

For pressures:

1 inch of mercury = 25.4 mm of mercury = 33.86 millibars
= 33.86 hectoPascals

For distances:

1 foot = 0.3048 meter
1 international nautical mile = 1.1508 statute miles
= 1.852 kilometers = .99933 U.S nautical mile (obsolete)
1° latitude = 69.047 statute miles = 60 nautical miles
= 111.12 kilometers
For longitude the conversion is the same as latitude except the value is multiplied by the cosine of the latitude.

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