Friction reduces the predicted speed somewhat, but the basic principle explains the high rotational velocities near the center of the storm. As the air moves away from the center, its counterclockwise rotation slows, in accord with conservation of angular momentum. At a distance of about 190 mi from the center, the air acquires a clockwise rotation. Hurricanes move with the large-scale wind currents in which they are embedded. The typical speed is 16 mph, but some storms may race along at twice this speed, and others can remain stalled in the same location for several days.
Typical tracks are from east to west at low latitudes.
As the storms approach the continental land masses, they usually begin to take a more northerly tack. As they reach higher latitudes and come under the influence of the westerlies, they usually turn toward the northeast, often missing the continents. This turn, the northeast, is called recurvature. Until 1944, when hurricane reconnaissance by aircraft became common, detection of hurricanes was based entirely on surface reports of land stations or ships, and some small storms probably went unnoticed. Although aircraft reconnaissance has considerably improved the ability to detect and monitor tropical storms, the greatest advance in early detection has been the continuous surveillance maintained by the series of geosynchronous satellites stationed over fixed points on the equator.