A weather map provides a view of weather elements over a specified geographical area at a specified time and was invented by Sir Francis Galton.
Look at the on the left.
It shows the weather for Thursday (15/6/00).
Predict which day of the following weekend would be the best day to have a picnic in Melbourne, Saturday(17/6/00) or Sunday(18/6/00)?
One of the tools that forecasters use to identify and locate air masses, pressure systems, and fronts is the weather map. These maps are normally prepared at 3- or 6-hour intervals.
s that are produced for the portion of the atmosphere above the lower troposphere, generally at and above 850 mb. Isolines on these maps usually represent the heights of a constant pressure surface, such as the 500 mb surface.
Use a weather map to look up the temperatures of cities around the world and discover how hot each gets in the summer and how cold each gets in the winter. Compare these figures with your town.
Line on a joining points of equal pressure.
Lines drawn through positions with the same temperatures.
Upper-air weather maps differ from surface weather maps. Whereas surface weather conditions are plotted on a map of constant altitude (normally sea-level), upper-air weather conditions are plotted on maps of constant air pressure.
A line on a linking areas with equal air pressure
Low Pressure ...
Weather services like WeatherOnline or the Met Office are using the data for plotting weather maps, such as the mean-sea-level pressure chart, which is also known simply as surface chart.
A line drawn on a connecting points of equal pressure is called an "isobar". Isobars are generated from mean sea-level pressure reports and are given in millibars.
Isobar- A line on a weather map that surrounds an area with the same atmospheric pressure.
Isotherm- A line on a weather map that surrounds an area with the same temperature.
The line drawn on a connecting points of equal barometric pressure.
The line drawn on a connecting points of equal dew point.
after the flare maximum, and can last for hoursRadio EventFlares with Centimetric Bursts and/or definite Ionospheric Event (SID)RadiofacsimileAlso known as HF FAX, radiofax or weatherfax, is a means of broadcasting graphic weather maps and ...
Station ModelA specified pattern for plotting, on a , the meteorological symbols that represent the state of the weather at a particular observing station.Station PressureThe absolute air pressure at a given reporting station.
Cold PoolA region of relatively cold air, represented on a weather map analysis as a relative minimum in temperature surrounded by closed isotherms.
Isobaric ChartA representing conditions on a surface of equal atmospheric pressure. For example, a 500 mb chart will display conditions at the level of the atmosphere at which the atmospheric pressure is 500 mb.
A continental cold air mass is a high pressure center, and it is represented on the weather map by the capital letter "H". It will change as it moves southward, and will become a "transformed continental air mass" when it reaches east China.
The isobars on a are usually drawn with a 4 mb contour interval, so to get the pressure gradient we multiply the above figure by 4 divided by the distance between the isobars in degrees of latitude.
upper-air weather chartWeather maps that are produced for the portion of the atmosphere above the lower troposphere, generally at and above 850 millibars.
Constant Pressure Maps: A of a particular constant pressure surface, such as the 50 kPa or 500 mb surface, in which atmospheric pressure is uniform everywhere.
Isopleth A line on a weather map connecting constant thickness (layer of atmosphere).
Isotach A line on a weather map connecting points of equal wind speed.
Isotherm A line on a weather map connecting points of equal temperature.
ISODROSOTHERM The line drawn on a connecting points of equal dew point.
ISOHEL A line drawn through geographic points having equal duration of sunshine or another form of solar radiation during a specified time period.
ISOBAR: A line of equal barometric pressure on a weather map.
ITCZ: Inter-tropical Convergence Zone.
Isobar - A line on a that connects points of equal pressure. On a , isobars extend around areas of high and low pressure.
Isobars Lines drawn on a weather map joining places of equal barometric pressure.
Isothermal Of or indicating equality of temperature.
Isotherms Lines connecting points of equal temperature on a weather map.
Isobar- the line of equal pressure denoted on surface s.
Isotherm- the line of equal temperature denoted on surface s.
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Air pressure tendency - Change in air pressure with time; on a surface weather map, the air pressure change over the prior 3 hours.
Albedo - The fraction or percent of radiation striking a surface that is reflected by that surface.
Most high and low pressure areas seen on s are synoptic-scale systems.
NOAA National Weather Service - Cite This Source - This Definition ...
Synoptic scale The typical weather map scale that shows features such as high- and low-pressure areas and fronts over a distance spanning a continent. Also called the cyclonic scale.
Low: A region of low pressure, marked as "L" on a . A low center is usually accompanied by precipitation, extensive cloudiness, and moderate winds. See Cyclone.
synoptic chart—A chart, such as the familiar weather map, which depicts the distribution of meteorological conditions over an area at a given time.
target—In radar, any of the many types of objects detected by radar.
The saddle point (sometimes called a "col") refers to a point in the air pressure pattern depicted on a .
'the air temperature' and it is these values that appear, for example, in the World Cities reports in newspapers/teletext, or plotted on standard synoptic charts, and also it is at this level that the forecast temperatures seen on tv weather maps are ...
Fronts: In temperate climates air mass discontinuities are demarcated by Fronts . These are not featured on the Malawi .
Surface convergence: An upwelling of excess air as air streams from different directions converge.
Geostrophic wind - a theoretical wind which blows along the isobars on a weather map. Pretty good of actual winds high above the ground.
col - (Also called saddle point, neutral point.) In meteorology, the point of intersection of a trough and a ridge in the pressure pattern of a .
ISOBAR - A line connecting equal points of barometric pressure, which are usually depicted on weather maps and charts by meteorologists.
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INVERTED TROUGH - A trough of low pressure appearing as an "upside down" trough on a . These are troughs where the flow they are embedded in is from an Easterly direction in the Northern hemisphere.
Synoptic Scale (or Large Scale) - Size scale referring generally to weather systems with horizontal dimensions of several hundred miles or more. Most high and low pressure areas seen on weather maps are synoptic-scale systems.
WaveIn meteorology any pattern identifiable on a that has a cyclic pattern or a small cyclonic circulation in the early stages of development that moves along a cold front.
See also: Weather, Air, Pressure, Surface, Temperature