This article is about the wind. For other uses, see Gale (disambiguation).
A gale is a very strong wind. There are conflicting definitions of how strong a wind must be to be considered a gale. The U.S. National Weather Service defines a gale as 34-47 knots (63-87 km/h, 17.5-24.2 m/s or 39-54 miles/hour) of sustained surface winds. Forecasters typically issue gale warnings when winds of this strength are expected.
Other sources use minima as low as 28 knots (52 km/h, 32 mph) and maxima as high as 90 knots (170 km/h, 100 mph). Through 1986, the National Hurricane Center used the term gale to refer to winds of tropical force for coastal areas, between 33 knots (61 km/h, 38 mph) and 63 knots (117 km/h, 72 mph). The 90-knot (170 km/h) definition is very non-standard. A common alternative definition of the maximum is 55 knots (102 km/h, 63 mph).
The most common way of measuring winds is with the Beaufort scale /ˈboʊfərt/, which defines gale as wind from 50 to 102 km/h. It is an empirical measure for describing wind speed based mainly on observed sea conditions. Its full name is the Beaufort Wind Force Scale.
On the Beaufort Wind Scale, a Gale is classified as: Moderate Gale (32-38 miles per hour), Fresh Gale (39-46 mph), Strong Gale (47-54 mph) and Whole Gale (55-63 mph). A Gale is a type of Wind Description preceded by Calm, Light Air, Light Breeze, Gentle Breeze, Moderate Breeze, Fresh Breeze, Strong Breeze and succeeded by Storm,Violent Storm and Hurricane on a Beaufort Wind Scale. There is a unique Beaufort Scale number and a unique Arrow Indication for each type of Wind Description mentioned above.
The word gale is derived from the older gail, but its origin is uncertain.