Quantcast Identification of Weather Echoes Using A PPI Scope

Order this information in Print

Order this information on CD-ROM

Download in PDF Format


Click here to make tpub.com your Home Page

Page Title: Identification of Weather Echoes Using A PPI Scope
Back | Up | Next

tpub.com Updates




Information Categories
.... Administration
Food and Cooking
Nuclear Fundamentals
  Educational CD-ROM's
Printed Manuals
Downloadable Books


Back ] Home ] Up ] Next ]

Click here to Order your Radar Equipment Online

Identification of Weather Echoes Using A PPI Scope

The plan position indicator (PPI) scope provides range and bearing information on weather echoes. Figure 10-4-1, views A and B, illustrates precipitation echoes as seen on a PPI scope. A standard scope presentation is shown in view A, and a contoured echo display is shown in view B. The latter is a feature available on many of

Figure 10-4-1.—Precipitation echoes as seen on a PPI scope. A. Typical PPI showing convective precipitation echoes and ground clutter. Range markers are every 25 nautical miles. B. Contoured echo display on PPI of same echoes.

today’s weather radars. The intensity levels are color coded, thereby permitting a quick deter-mination of intensity gradients (strong to weak, weak to strong, etc.) and maximum intensities. Weather echoes are classified according to their cinfiguration, coverage, continuity of pattern, and meteorological processes. The echo systems are then grouped for ease in reporting, according to the following definitions:

. AREA—Related or similar echoes that can be readily associated geographically.

. LINE—Related or similar convective echoes having a length-to-width ratio of at least 5 to 1. The line must be at least 30 nautical miles long.

. CELL(S)—One or more convective echoes that, for reasons of isolation, intensity, or character, cannot be grouped with other echoes. 

. STlLATIFIED ELEVATED ECHO—Pre-cipitation aloft. 

. SPIRAL BAND AREA—Echoes asso-ciated with tropical storms and hurricanes/ typhoons and systematically arranged in curved lines. These echoes may include a wall cloud.

. EYE—A well-defined central region of a tropical storm or hurricane.

. CENTER—A poorly defined central region of a tropical storm or hurricane.

. FINE LINE—A narrow nonprecipitation echo pattern associated with the cold air outflow in advance of a squall line or the leading edge of a sea breeze front.

The appearance of echoes on a PPI scope can give you some idea of the weather to which they are related. For instance, scattered echoes may be related to air-mass weather; lines of convective echoes may be related to squall lines or fronts; certain characteristic curves in echo lines maybe related to frontal waves; and widespread relatively uniform echo patterns may be related to stable warm frontal precipitation. Now, let’s discuss the appearance of some specific weather phenomena on the PPI scope.

Back ] Home ] Up ] Next ]


Privacy Statement - Press Release - Copyright Information. - Contact Us - Support Integrated Publishing

Integrated Publishing, Inc.