A Gulf low or Texas Low is a

low pressure area In meteorology, a low-pressure area, low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. Low-pressure areas are commonly associated with inclement weather (such as cloudy, windy, with possible ...

that forms or intensifies over the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United ...

and move northeast on the western side of the

Appalachian mountains The Appalachian Mountains, often called the Appalachians, (french: Appalaches), are a system of mountains in eastern to northeastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician Period. They ...

and sometimes on the Atlantic coast to become a

nor'easter A nor'easter (also northeaster; see below), or an East Coast low is a synoptic-scale extratropical cyclone in the western North Atlantic Ocean. The name derives from the direction of the winds that blow from the northeast. The original use ...

. Because they move from over or near the Gulf of Mexico, these storm systems are capable of transporting copious amounts of moisture with them. At their strongest, these storm systems are even more potent snowfall producers than

panhandle hook A panhandle hook (also called a pan handle hook or Texas hooker) is a relatively infrequent winter storm system whose cyclogenesis occurs in the South to southwestern United States from the late fall through winter and into the early Spring (seaso ...

s, primarily because of the mixing of Atlantic Ocean moisture into the storm system once they cross the Appalachian Mountains. Because of the general west to east movement of weather systems in the mid latitudes of the northern hemisphere, Gulf Lows rarely affect areas west of the

Mississippi River The Mississippi River is the second-longest river and chief river of the second-largest drainage system in North America, second only to the Hudson Bay drainage system. From its traditional source of Lake Itasca in northern Minnesota, it fl ...

. One such exception was the Halloween Blizzard of 1991.

Types

There are two types of "Gulf Lows": West and East Gulf Cyclones or Types Ga and Gb.as per the

California Institute of Technology The California Institute of Technology (branded as Caltech or CIT)The university itself only spells its short form as "Caltech"; the institution considers other spellings such a"Cal Tech" and "CalTech" incorrect. The institute is also occasional ...

(CIT) As western storms (

Alberta clipper An Alberta clipper, also known as an Alberta low, Alberta cyclone, Alberta lee cyclone, Canadian clipper, or simply clipper, is a fast-moving low-pressure system that originates in or near the Canadian province of Alberta just east of the Rock ...

s, North and South Pacific and Rocky Mountain) move eastward, a trailing frontal remnant is often left in the Gulf of Mexico or the adjacent coastal states. When the frontal trough from a new cyclone enters this area,

cyclogenesis Cyclogenesis is the development or strengthening of cyclonic circulation in the atmosphere (a low-pressure area). Cyclogenesis is an umbrella term for at least three different processes, all of which result in the development of some sort of cycl ...

often occurs on the Gulf front. This newly formed Gulf wave that moves northeastward and dominates the weather over the eastern United States and Canada. One of the basic differences between the two types is that the Ga track is west of the Appalachians and the Gb track is east of the Appalachians.

Ga

The Ga type is characterized by an upper-level trough in the central and eastern part of the United States which steers the newly formed wave north and northeast over the western side of the Appalachians accompanied by widespread precipitation to the north. This type is most frequently observed in the winter and early spring.

Gb

The

1993 North American Storm Complex The 1993 Storm of the Century (also known as the 93 Superstorm, The No Name Storm, or the Great Blizzard of '93/1993) was a cyclonic storm that formed over the Gulf of Mexico on March 12, 1993. The cold weather, heavy snowfall, high winds and st ...

started out as a Gulf Low (East Gulf Low or Gb) before it eventually evolved into a

. It initially formed in the western Gulf of Mexico and moved towards Florida before turning to the north and becoming a nor'easter. Another large gulf low storm was the Great Blizzard of 1978, which brought one of the lowest non-tropical barometric pressures recorded in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

References

{{Extratropical cyclones Extratropical cyclones fr:Tempête synoptique continentale américaine#Dépression du Golfe du Mexique

Types

Ga

Gb

See also

References