Low

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.

Low-level clouds (St, Sc, Ns) Stratus, Stratocumulus, and in some degree, Nimbostratus are low clouds.

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).

Cold low (ger: Kältetief; fr: dépression froide)
Also known as a cold pool, or a polar lows, these terms refer to areas of low pressure and temperature in the middle troposphere.

low water"(Popularly called low tide.) The minimum water level reached in a tidal cycle.

Low Level Jet: A relatively narrow band of high-speed winds found in the lower troposphere, well below the upper troposphere where the jet stream is found.
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low level clouds
stratus (unbroken layer of cloud), nimbostratus (dark, unbroken layer, rain cloud)
cumulus (puffy, irregular clouds), stratocumulus (cumulus clouds arranged in a broad layer)
clouds of vertical development ...

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 cloud - See cloud classification.
lower atmosphere - Generally and quite loosely, that part of the atmosphere in which most weather phenomena occur (i.e., the troposphere and lower stratosphere); ...

Low clouds
Clouds with bases below 6000 feet and are stratiform or cumuliform in variety.
Low latitudes ...

LOW: The center of an area of low pressure, usually accompanied by cyclonic and inward wind flow. Also known as a cyclone.
MARITIME AIR MASS: Moist air mass originating over the ocean.

LOW LEVEL WIND SHEAR: A local variation in the wind direction or speed. This condition can present danger to aircraft, especially at landing, when a sudden shift from headwind to tailwind can cause a rapid loss of airspeed and lift.

Low Pressure - 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 A region of low pressure, marked as "L" on a weather map. A low center is usually accompanied by precipitation, extensive cloudiness, and moderate winds. See cyclone.

low clouds: clouds found between the earth's surface and 2 kilometers (0-6500 feet) in all geographic regions. Contains stratocumulus and stratus clouds, and sometimes nimbostratus, cirrus and cumulonimbus clouds.

Low Level Jet - A jet stream that is typically found in the lower 2-3 km, or approximately 6,000 to 9, 500 feet, of the troposphere.

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- The center of an area of low pressure, accompanied by cyclonic and inward wind flow in the northern hemisphere. Also known as a cyclone.
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low—An area of low barometric pressure, with its attendant system of winds. Also called a barometric depression or cyclone.
M
mammato cumulus—Obsolete. See cumulonimbus mamma.

Low-level Jet (abbrev. LLJ) - A region of relatively strong winds in the lower part of the atmosphere.

Low or Low-Pressure System A horizontal area where the atmospheric pressure is less than it is in adjacent areas.

LOW CLOUDS
A term used to signify clouds with bases below 6,000 feet and are of a stratiform or a cumuliform variety. Stratiform clouds include stratus and stratocumulus. Cumuliform clouds include cumulus and cumulonimbus.

Low-level jet - [abbrev LLJ] A region of relatively strong winds in the lower part of the atmosphere.

LP- Low Precipitation Supercell. This is a supercell that lacks abundant moisture. They occur around a dryline boundary where moisture depth is greatly reduced. They tend to look much more severe in the field than they do on radar.

WARM LOW
A low pressure system that has its warmest temperatures at or near the center of circulation. Also referred to as a warm core low.

Cold Low- a low pressure system with cold air mass from near the surface to all vertical levels (also called a cold core low).

Very Low Frequency (VLF)
That portion of the radio frequency spectrum from 3 to 30 kHz
Very Windy ...

Mean Low Water (MLW): The average height of the daily low tides recorded over a 19-year period at a specific location.

Closed Low - A low pressure area with a distinct center of cyclonic circulation which can be completely encircled by one or more isobars or height contour lines.

Cutoff low Cyclonic circulation system that separates from the prevailing westerly airflow and therefore remains stationary.
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Daily range of temperature The difference between the maximum and minimum temperatures for any given day.

THERMAL LOW Also known as heat low, it is an area of low pressure due to the high temperatures caused by intensive heating at the surface. It tends to remain stationary over its source area, with weak cyclonic circulation.

Low-level warm advection sometimes is referred to (erroneously) as overrunning. Although the two terms are not properly interchangeable, both imply the presence of lifting in low levels.

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- a system in which air pressure decreases toward the center, associated with unsettled weather, usually formed by a mass of warm air being forced up by cold air.

LOW: A cyclonic storm that often forms along a front, around which the wind blows counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.
METEOROLOGY: The study of atmospheric phenomena.

Low- An area of low atmospheric pressure.
Maritime Air Mass- An air mass that forms over water. It is usually humid, and may be cold or warm.

LOW PRESSURE AREA - An area of low atmospheric pressure which generally means poor visibility for flying.
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Low cloud covering hills and giving a visibility below 200 metres.
Hoar Frost
Ice crystals deposited on objects below 0 degrees Celsius or dew that freezes after formation.

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 LEVEL - Region of the atmosphere from the earth's surface to 6,500 feet.
LOW PRESSURE - A region of low air pressure in the atmosphere. Commonly associated with storms and cyclones.

1. Low Clouds: Surface to 6,500 ft..........
2. Middle Clouds: 6,500 ft. to 18,000 ft...
3. High Clouds: 18,000 to 30,000 ft.........

See low.
Design Wave Height
The wave height adopted for the purposes of designing coastal structures such as breakwaters and seawalls. It is chosen to ensure that the structures are not at undue risk of wave damage.

Remnant Low: Used for systems no longer having convection required of a tropical cyclone (e.g., the swirls of stratocumulus in the eastern North Pacific).

In the 'Low' cloud classification come: Stratus (St); Stratocumulus (Sc); Cumulus (Cu) and Cumulonimbus (Cb).

Aleutian Low - A large cell of low' pressure centered over the Aleutian Islands of the North Pacific during the winter.
Altimeter - An aneroid barometer calibrated to indicate altitude instead of pressure.

Aleutian low The subpolar low-pressure area that is centered near the Aleutian Islands on charts that show mean sea level pressure.

Subpolar low High-latitude, semipermanent cyclones marking the convergence of planetary-scale surface southwesterlies of midlatitudes with surface northeasterlies of polar latitudes; Icelandic low and Aleutian low are examples. ...

Eye: The low pressure center of a tropical cyclone. Winds are normally calm and sometimes the sky clears. ...

A cyclone or low is an area of closed isobars surrounding an area of lower pressure. The wind blows along the isobars in the direction in which the pressure gradient balances the Coriolis force.

Scud Clouds - Low cloud fragments often seen in association with and behind thunderstorm gust fronts. these clouds are ragged and wind-torn and are not usually attached to the thunderstorm base. Scud clouds do not produce severe weather.

Dry Air
Air of low relative humidity.
Dry Snow
Snow from which a snowball cannot readily be made and which has a temperature less than zero degrees Celsius.

Roll Cloud - A low, horizontal, tube-shaped cloud associated with a thunderstorm gust front. Roll clouds are completely detached from the base of the thunderstorm and appear to be "rolling" about a horizontal axis.

They are low level occurances, usually only ten feet in height to not more than fifty feet above the surface. Due to the frequent winds created by surface heating, they are most predominate during the day and die out in the night.

Scud Ragged low clouds, usually stratus fractus. Most often applied when such clouds are moving rapidly beneath a layer of nimbostratus.

TThunderstormT RollsTransverse Rolls - elongated low-level clouds, arranged in parallel bands and aligned parallel to the low-level winds but perpendicular to the mid-level flow.

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 ...

Nearshore Forecast(NSH) - National Weather Service seasonal marine forecasts for an areas of the Great Lakes extending from a line approximating mean low water datum along the coast or an island, including bays, harbors, and sounds, out to 5 nm.

Occluded MesocycloneA mesocyclone in which air from the rear-flank downdraft has completely enveloped the circulation at low levels, cutting off the inflow of warm unstable low-level air.

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.

See also: Air, High, Pressure, Weather, Cloud