Closed Low – Definition

Closed Low

A region of low pressure distinguished by a center of counterclockwise circulation (in the Northern Hemisphere), and is surrounded by one or more isobars or height contours. Closed lows aloft (i.e., above the surface) may become disconnected from the primary westerly flow and thus progress eastward more slowly. It is important to note that a cutoff low is a closed low, but not all closed lows are cutoff lows.

Low Pressure System

An area of a relative pressure minimum that has converging winds and rotates in the same direction as the earth. This is counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. Also known as an cyclone, it is the opposite of an area of high pressure, or a anticyclone.

Isobar

The line drawn on a weather map connecting points of equal barometric pressure.

Westerlies

Usually applied to the broad patterns of persistent winds with a westerly component. It is the dominant persistent atmospheric motion, centered over the midlatitudes of each hemisphere. Near the earth’s surface, the westerlies extend from approximately 35 to 65 degrees latitude, while in the upper levels they extend further polarward and equatorward.

Cut-Off Low

A closed cold core low completely removed from the primary westerly flow. Cutoff lows may remain detached from the westerlies for days while exhibiting very little forward (eastward) progress. In some instances, a cutoff low may move to the west, or retrograde, opposite to the prevailing flow. It is important to note that a cutoff low is a closed low, but not all closed lows are cutoff lows.

Service Area

Broward County: Andytown, Bonnie Loch-Woodsetter North, Boulevard Gardens, Broadview-Pompano Park, Broward Estates, Carver Ranches, Chambers Estates Chula Vista Isles, Coconut Creek, Collier Manor-Cresthaven, Cooper City, Coral Springs, Country Estates, Crystal Lake, Dania Beach, Davie, Deerfield Beach, Edgewater, Fort Lauderdale, Franklin Park, Golden Heights, Green Meadow, Hacienda Village, Hallandale Beach, Hillsboro Beach, Hillsboro Pines, Hillsboro Ranches, Hollywood, Ivanhoe Estates, Kendall Green, Lake Forest, Lauderdale-by-the-Sea, Lauderdale Lakes, Lauderhill, Lazy Lake, Leisureville, Lighthouse Point, Loch Lomond, Margate, Melrose Park, Miramar, North Andrews Gardens, North Lauderdale, Oak Point, Oakland Park, Palm Aire, Parkland, Pembroke Park, Pembroke Pines, Pine Island Ridge, Plantation, Pompano Beach, Pompano Beach Highlands, Pompano Estates, Ramblewood East, Ravenswood Estates, Riverland Village, Rock Island, Rolling Oaks, Roosevelt Gardens, Royal Palm Ranches, Sea Ranch Lakes, Southwest Ranches, St. George, Sunrise, Sunshine Acres, Sunshine Ranches, Tamarac, Tedder, Terra Mar, Utopia, Village Park, Washington Park, West Ken-Lark, West Park, Weston, Wilton Manors

Counties: Brevard, Broward, Collier, Hendry, Indian River, Lee, Martin, Miami-Dade, Monroe, Palm Beach, St Lucie

412 Sunshine Blvd
Tavernier,
FL
33070