Issued when hazardous weather or hydrologic conditions exist, are imminent or are likely to occur. Advisories are issued for conditions that may cause major inconvenience and could lead to situations that may threaten life or property. An area of high pressure. Winds blow in a clockwise direction in the Northern Hemisphere and in a counter clockwise direction in the Southern Hemisphere.
Fair weather is associated with an anticyclone.
A front that moves east to west in direction rather than normal west to east movement. A wind that changes its direction in a counter clockwise motion. An example would be a Northwest wind changing to a West wind. Under 1 Calm, smoke rises vertically. 1 1-3 Smoke drift indicates wind direction, vanes do not move.