Search results
Results from the WOW.Com Content Network
A surface weather analysis for the United States on October 21, 2006. By that time, Tropical Storm Paul was active (Paul later became a hurricane). Surface weather analysis is a special type of weather map that provides a view of weather elements over a geographical area at a specified time based on information from ground-based weather stations.
Two-dimensional streamlines based on wind speeds at various levels show areas of convergence and divergence in the wind field, which are helpful in determining the location of features within the wind pattern. A popular type of surface weather map is the surface weather analysis, which plots isobars to depict areas of high pressure and low ...
In meteorology, prevailing wind in a region of the Earth's surface is a surface wind that blows predominantly from a particular direction. The dominant winds are the trends in direction of wind with the highest speed over a particular point on the Earth's surface at any given time.
The earliest surface analyses from the United States featured a map of the continental U.S. with indications of cloud cover and wind direction arranged on an early form of what has become a station model. A general indication of the weather for various cities around the country was also included on the bottom of the map.
On the top right corner of the model for a surface weather map is the pressure, showing the last two integer digits of the pressure in millibars, or hectopascals, along with the first decimal. For instance, if the pressure at a certain location is 999.7 hPa, the pressure portion of the station model will read 997.
Two-dimensional streamlines based on wind speeds show areas of convergence and divergence in the wind field, which are helpful in determining the location of features within the wind pattern. A popular type of surface weather map is the surface weather analysis, which plots isobars to depict areas of high pressure and low pressure.
The station model plotted on surface weather maps uses a wind barb to show both wind direction and speed. The wind barb shows the speed using "flags" on the end. Each half of a flag depicts 5 knots (9.3 km/h; 5.8 mph) of wind. Each full flag depicts 10 knots (19 km/h; 12 mph) of wind.
The Santa Anas are katabatic winds (Greek for "flowing downhill") arising in higher altitudes and blowing down towards sea level. [7] The National Weather Service defines Santa Ana winds as "a weather condition [in southern California] in which strong, hot, dust-bearing winds descend to the Pacific Coast around Los Angeles from inland desert regions".