Gale - In storm warning, this term applies to winds of 32-54 mph, while in the Beaufort wind scale it covers winds of 32-63 mph.
Galerne - A cold, humid, squally northwest wind also accompanied by showers occurring behind a low pressure area in the
Gap Wind - A low-level, strong wind which blows through either a fairly level channel between two mountain ranges or which blows through a gap in a mountain barrier.
Garbin - A southwesterly sea breeze beginning about in southwest
Garua - On the western coast of
Graphic of GOES-I-M the present generation of GOES-NEXT Satellites
From NOAA Photo Library
Geostationary Operational Environmental Satellite - Abbreviated GOES, this type of satellite orbits exactly over the Earth's equator and rotates at the same speed as the Earth so that it remains over the same spot.
Glaciation - In meteorology, the change which takes place when supercooled water droplets in a cloud turn to ice crystals.
Glaze - The coating of clear ice which forms on exposed surfaces with temperatures at or below 32 degrees Fahrenheit during an episode of freezing rain (rain which consists of supercooled water drops).
Glory - An optical phenomenon consisting of small, faintly colored rings of light which surround the antisolar point and seen when looking down on clouds consisting of water droplets.
Graupel (also called Snow Pellets or Tapioca Snow)
Graupel - Small pellets of ice (often known as snow pellets), which are made by supercooled water droplets coating snowflakes with a layer of rime. The pellets are cloudy or white and not clear.
Green Flash - A flash of green light seen either on or apparently adjacent to the upper rim of the sun when it is low in the sky at sunrise or sunset. It is actually a mirage caused by displacement, distortion and dispersion.
Green Snow - Snow which acquires a greenish hue due to the growth within it of microscopic algae known as cryoplankton.
Greenhouse Effect - Warming of the atmosphere due to the trapping of earth's longwave radiation as it is being radiated to space. Water vapor and carbon dioxide are the chief gases responsible for this. Ozone, methane, nitrous oxide and chlorofluorocarbons also contribute to the greenhouse effect.
Gregale - The Maltese name for the strong northeast wind over central and western parts of the Mediterrranean Sea and the adjoining land areas of Europe.
Ground Fog - In U.S. Weather observing practice, this is a fog which does not extend to any cloud bases which may be above it and hides less than 0.6 of the sky.
Ground-to-Cloud Lightning Discharge.
Ground-to-Cloud Discharge - A lightning discharge in which the initial leader starts upward from some object on the ground.
Growing Season - In general, the growing season is that part of the year in which temperatures of cultivated plants remain sufficiently high to allow growth. The most common method of measuring this period is from the date of the last killing frost in spring to the date of the first killing frost in autumn.
Gust - A sudden, brief increase in the wind speed usually lasting less than 20 seconds with a fluctuation greater than 10 mph.
Gust Front - The leading edge of a thunderstorm downdraft.
Gustnado - A small, usually weak and short-lived tornado occurring along a thunderstorm gust front.
Haar - A wet sea fog or drizzle which comes in from the sea along coasatal areas of northeastern England and eastern Scotland.
Haboob - A haboob, which means "wind" in Arabic, is a strong wind and duststorm or sandstorm in northern and central Sudan, Africa.
Hail - Precipitation in the form of fairly round balls or irregularly shaped lumps of ice.
Hailpad - Usually consisting of plastic foam covered either with aluminum foil or white latex paint and put in a frame which is pounded into the ground, the hailpad is used for measuring the size distribution and mass of hailstones.
Hailstone and walnut for comparison.
Hailstone - An individual unit of hail which may range in size from that of a pea to that of a grapefruit or larger.
Hailstorm - Although a hailstorm can refer to any storm which produces hailstones that reach the ground, the term is usually used only when the size and/or amount of hailstones is considered significant.
Hair Hygrometer - An instrument which measures relative humidity according to the variations in length of a strand of human hair.
Halo - The name given to a variety of either white or colored rings, arcs, pillars, or spots of light around or near the sun or moon and which are caused by either reflection or refraction of light by ice crystals.
Halo of 46 degrees - A halo which appears as either a circle or part of a cirlce around either the sun or moon and whose angular radius is about 46 degrees.
22 Degree Halo by C. Devon Collins.
Halo of 22 degrees - A halo around either the sun or moon appearing in the form of either a circle or partial circle with an angular radius of 22 degrees.
Harmattan - A wind originating in the Sahara Desert and which blows from the northeast or east in West Africa. This wind occurs most frequently between late November and the middle of March, and it is a dust-bearing, dry wind.
Haze - A phenomenon caused by particles suspended in the air and reducing visibility due to the scattering of light.
Haze Droplet - A small liquid droplet of any kind which is less than a micrometer (.00003937 inch) in diameter and which contributes to atmospheric haze.
Heat Index - An index which combines relative humidity with air temperature to yield an apparent temperature of how hot conditions feel.
Heat Lightning - Not a real type of lightning but rather a colloquial term for the luminosity of ordinary lightning from a storm too far away for thunder to be heard.
Heat Wave - A period of weather which is both uncomfortably and abnormally hot and which is often humid as well. Such a period must last at least one day in order to be classified as a heat wave, but a heat wave usually lasts from a few days to several weeks.
Heating Degree Day - One heating degree day is given for every degree the average daily temperature falls below 65 degrees Fahrenheit.
Heavy Snow - In weather observing practice, snow is said to be heavy when visibility is less than 5/16 of a mile, or 1/2 kilometer.
Hectopascal - A unit used in reporting atmospheric pressure and abbreviated hPa, it is equal to 100 pascals or 1 millibar (.0295299 inch).
Helicity - A concept useful in understanding severe thunderstorms. It is that property of a moving fluid (in meteorology that fluid is the air) which shows the potential for the development of corkscrew like flow (and thus rotation).
Helm Wind - A wind which blows down into the Eden Valley from the western slope of the Crossfell Range in northern England. This northeasterly wind is cold and strong and occurs when the general wind direction is somewhere between north-northeast and east. The cloud line which then forms along the crest of the ridge is known as the helm.
High - An area of high atmospheric pressure; an anticyclone.
Hoarfrost - A deposit of ice crystals formed in the same manner as dew except that the temperature of the objects on which it forms must be below 32 degrees Fahrenheit, and the dew point temperature of the air must also be below the freezing mark.
Hodograph - A plot which represents the vertical distribution of the horizontal wind.
Hook Echo Norman Oklahoma March 29,1988 Photo from NOAA Photo Library
Hook Echo - A pattern shaped somewhat like a fishhook turned toward the east on a radar screen. It is located in the southwest quadrant of a tornadic thunderstorm and is caused by precipitation aloft around the edges of a rotating column of air (the mesocyclone) in the thunderstorm.
Horse Latitudes - The area over the oceans between 30 and 35 degrees north and south latitude where winds are either very light or calm, and the weather is dry and hot.
Humidity - A measure of the water vapor content of the atmosphere.
Hurricane Katrina August 28, 2005 - NASA photo.
Hurricane - A tropical cyclone whose one minute average surface winds exceed 64 knots (74 m.p.h.).
Hygrometer - An instrument used to measure the water vapor content of the atmosphere.
Hygroscopic Nucleus - A particle which is either somewhat water absorbant or has an attraction for water and which serves as a center for water condensation.
Copyright 2006 Ronald Hahn. All Rights Reserved