Buys Ballot's Law calls this the Dangerous Quadrant.

Buys Ballot's law states that if a person in the Northern Hemisphere stands with his back to the wind, the low atmospheric pressure is found to his left.

Buys Ballot's law, which was first deduced by the American meteorologists J.H. Coffin and William Ferrel, is a direct consequence of Ferrel's law.

Together with William Ferrel, he deduced the Buys Ballot's law, which was named after the Dutch meteorologist C. H. D. Buys Ballot.

Although the principles here to a very limited extent apply to a coastal observer during the approach and passage of a storm in any location, Buys Ballot's Law was primarily formulated from empirical data to assist ships at sea.

These observations and application of the principles of Buys Ballot's Law help to establish the probability of the existence of a storm and the best course to steer to try avoid the worst of it-with the best chance of survival.

From a slightly less esoteric standpoint the underlying principles of Buys Ballot's Law states that for anyone ashore in the Northern Hemisphere and in the path of a hurricane, the most dangerous place to be is in the right front quadrant of the storm.

Included in the "Sailing Directions for the World" are Buys Ballot's Law techniques for avoiding the worst part of any rotating storm system at sea using only locally observable phenomena i.e. cloud formations, wind speed and barometric pressure tendencies over a number of hours.

The barbs in the figure at the right are located at the Northern Hemisphere, because the wind is circling counter clock-wise around a low-pressure area at the Northern Hemisphere (the wind is blowing in the opposite direction at the Southern Hemisphere, see also Buys Ballot's law).