Low Pressure Centers also known as cyclones
A low pressure center is where the pressure has been measured to be the lowest relative to its surroundings.
A low pressure area, or a low for short, is a region where the atmospheric pressure is lowest with relation to the surrounding area.
Low pressure systems or mid-latitude cyclones are atmospheric circulations that rotate clockwise in the Southern Hemisphere (anti-clockwise in the Northern Hemisphere).
Low Pressure
A mass of air that presses down only weakly on the surface of the Earth because it is being warmed and it therefore less dense
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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.
low pressure system: area of minimum air pressure, and cyclonic air movement.
Low Pressure Area - or a "Low" An area of low atmospheric pressure that has a closed counter-clockwise circulation in the Northern Hemisphere. Also known as a cyclone.
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low (low pressure system): area with lower atmospheric pressure than its surrounding areas; this makes air from surrounding areas to flow into the low, the end result of which is probably cloudiness and precipitation.
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Low or Low Pressure Area- an area of low pressure usually characterized by clouds of precipitation caused by rising air; often related to inclement weather such as winds flowing counter clockwise and into the center of the low.
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BOMB- A low pressure system that decreases in central pressure by at least 24 millibars in a 24 hour period.
Low pressure systems that originate in the panhandle region of Texas and Oklahoma which initially move east and then "hook" or recurve more northeast toward the upper Midwest or Great Lakes region.
LOW PRESSURE AREA - An area of low atmospheric pressure which generally means poor visibility for flying.
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Low Pressure System - A whirling mass of warm, moist air that generally brings stormy weather with strong winds. When viewed from above, winds spiral into a low-pressure center in a counterclockwise rotation in the Northern Hemisphere.
LOW PRESSURE - A region of low air pressure in the atmosphere. Commonly associated with storms and cyclones.
A low pressure area which is warmer at its center than at its periphery. Tropical cyclones exhibit this temperature pattern. Unlike cold core lows, these lows produce much of their cloud cover and precipitation during the nighttime.
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A low pressure area with a distinct centre of cyclonic circulation which can be completely encircled by one or more isobars or height contour lines. The term is usually used to distinguish a low pressure area aloft from a low-pressure trough.
A low pressure system that develops over subtropical waters that initially has a non-tropical circulation, but in which some elements of tropical cyclone cloud structure are present. Subtropical cyclones can evolve into tropical cyclones.
A strong low pressure system that affects the Mid Atlantic and New England States. It can form over land or over the coastal waters.
High and low pressure are relative. There's no set number that divides high and low pressure. Wind is used to describe the prevailing direction from which the wind is blowing with the speed given usually in miles per hour or knots.
A region of low pressure. Air flows inwards and (on the northern hemisphere) counterclockwise around a low. A low centre is usually accompanied by precipitation and strong winds. Also called "depression".
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A low pressure system that has its coldest temperatures at or near the center of circulation, and is thermally barotropic with respect to a horizontal plane. Also known as a cold core low.
Eye: The low pressure center of a tropical cyclone. Winds are normally calm and sometimes the sky clears. ...
mesolow"A low pressure area on the mesoscale. It has been used to refer both to features observed within convective storms and features even larger in scale.
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Low: An area of low pressure: Cyclonic.
Low Drifting Snow: Snow that is blowing at a height of less the
6 feet above the ground reducing visibility below 7 miles.
LEE TROUGH- Low pressure which develops just east of the Rocky Mountains or Cascades. Often lee troughs become organized into mature cyclones as they develop eastward.
Low - An area of low pressure, usually accompanied by cyclonic and inward wind flow. Also known as a cyclone.
Low-level Jet - A region of relatively strong winds in the lower part of the atmosphere.
CYCLONE: An area of low pressure around which the wind circulates in a counterclockwise direction in the Northern Hemisphere. It usually produces wet weather. The term is also used for a hurricane in the Indian Ocean.
It blocks the movement eastward movement of low pressure areas (cyclones) at its latitude.Blowing DustDust that is raised by the wind to moderate heights above the ground to a degree that horizontal visibility decreases to less than seven miles.
CATALINA EDDY A weak low pressure circulation that may form off the Southern California coast. CEILING The lowest cloud layer that is reported as broken or overcast. If the sky is totally obscured, then it is the height of the vertical visibility.
The winds blow through low passes where major river valleys issue onto the seaways when strong east-west pressure gradients exist between the coast and the inland areas, with low pressure over the ocean.
A general increase in the central pressure of a low pressure system.Fire WindA thermally driven wind blowing radially inward toward a fire, ...
Pancake IceIn hydrologic terms, circular flat pieces of ice with a raised rim; the shape and rim are due to repeated collisionsPanhandle HookLow pressure systems that originate in the panhandle region of Texas and Oklahoma which initially ...
DeepeningA decrease in the central pressure of a surface low pressure system. The storm is intensifying.Deformation ZoneThe change in shape of a fluid mass by variations in wind, specifically by stretching and/or shearing.
Depression In meteorology, an area of low pressure; a low or trough.
Again, centrifugal force aids the formation of a core of low pressure that hurries air upwards. The tornado funnel effectively connects its lower end with the lower pressure above, like a giant vacuum-cleaner hose.
Hurricanes, typhoons, and willy-willies all start out as weak low pressure areas that form over warm tropical waters (e.g., surface water temperature of at least 80 °F). Initially, winds and cloud formations over the warm tropical waters are minimal.
A trough on a mean sea level pressure chart, (or an upper air contour chart) can be picked out by an arrangement of isobars (contours) which are concave towards an area of low pressure (low contour height) along a particular axis, ...
Aleutian low - The low pressure center located near the Aleutian Islands on mean charts of sea level pressure. It represents one of the main centers of action in the atmospheric circulation of the Northern Hemisphere.
This law is based on the known wind fields which circulate around low pressure and high pressure systems in the northern hemisphere. It is exactly reversed in the southern hemisphere.
ICELANDIC LOW A semi-permanent, subpolar area of low pressure in the North Atlantic Ocean. Because of its broad area and range of central pressure, it is an area where migratory lows tend to slow down and deepen.
NAO Index - This index measures the anomalies in sea level pressure between the Icelandic low pressure system and the Azores high pressure system.
Snow Advisory- This product is issued when a low pressure system produces snow that may cause significant inconveniences but do not meet warning criteria and if caution is not exercised could lead to life threatening situations.
Cyclone movement The spatial displacement of a center of low pressure caused by the local redistribution of mass in the atmosphere. The trajectory of the center is often altered by heating or cooling on the air column.
disturbance—In meteorology, applied rather loosely: (1) any low pressure or cyclone, but usually one that is relatively small in size; (2) an area where weather, wind, pressure, etc.
Low - in meteorology, an region of low pressure; see also cyclone
Low-Level Jet (abbreviated LLJ) - a region of relatively strong winds in the lower part of the atmosphere.
TROUGH: An elongated area of low pressure at the surface or aloft.
TULE FOG: Radiation fog in the Central Valley. It forms during night and morning hours in late fall and winter months following the first significant rainfall.
Aleutian Low: A semi-permanent, atmospheric low pressure centre located near the Aleutian Islands on charts of mean sea-level pressure. It is most intense in the winter.
The main difference, however, between a lake effect snow and a "standard" snow storm is that lake effect snow storms are not low pressure system storms.
Subpolar low A belt of low pressure located between 60° and 70° latitude. In the Northern Hemisphere, this "belt" consists of the Aleutian low in the North Pacific and the Icelandic low in the North Atlantic.
CYCLONE: An area of low pressure around which winds blow counterclockwise in the Northern Hemisphere. Also the term used for a hurricane in the Indian Ocean and in the Western Pacific Ocean.
Cyclone - An area of low pressure. Winds blow in a counter clockwise direction in the Northern Hemisphere and in a clockwise direction in the Southern Hemisphere. Inclimate weather is associated with a cyclone.
Southern Oscillation Index An indicator based on the pressure gradient between the quasi-stationary low pressure region and the center of a subtropical high pressure cell.
Trough - An area of low pressure. Cyclonically curving winds.
TUTT - Tropical Upper Tropospheric Trough.
Upwelling - A rising-up of colder water.
A physical law describing wind flow around high and low pressure.
Campbell-Stokes recorder
A sunshine recorder that focuses the sun?s rays through a glass sphere burning to a card.
Icelandic Low - A large cell of low pressure centered over Iceland and southern Greenland in the North Atlantic during the winter.
Ice Point - The temperature at which ice melts.
Cyclone - Circular wind pattern around a centre of low pressure. Clockwise in Southern Hemisphere and counter clockwise in the Northern Hemisphere, when viewed from above.
Trough: on a weather chart, a narrow, elongated area of relatively low pressure.Turbulence: irregular motion of the atmosphere, as indicated by gusts and lulls in the wind.
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Unstable air: see absolutely unstable air.
Subtropical Cyclone: A non-frontal low pressure system that has characteristics of both tropical and extratropical cyclones.
Hurricane Eye
The relatively calm area of extremely low pressure near the center of the storm. In this area, winds are light and the sky is often covered by clouds.
In the southern hemisphere, if one stands with their back to the wind, then the low pressure centre is approximately to the right-hand side and higher pressure on the left.
 See also: Pressure, Low, Air, Weather, High
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