The Wx-500 & Weather Radar - L3 Stormscope II Series User Manual

Storm Mapping Technology Chapter 2 - Storm Mapping Principles
THE WX-500 & WEATHER RADAR
The storm mapping technology used in the WX-500 is fundamentally
different than the technology used in weather radar. Weather radar
operates by transmitting UHF radio waves in the direction of interest
and then receiving echoes from water droplets, whereas the WX-500
operates by receiving signals already present in the atmosphere due
to electrical discharges. The WX-500 processor analyzes the unique
characteristics of these signals, their signal strength, and their
varying rates of recurrence to determine the location and intensity of
the thunderstorms that generated the discharges. The WX-500 can
receive radiated electromagnetic signals from electrical discharges
up to 200 nmi away.
One disadvantage of weather radar is that the cumulus stage of
a thunderstorm (usually precipitation free) is unlikely to appear
on weather radar; however, it generally does contain electrical
discharges which will be detected by the WX-500 as a light but
increasing cluster of discharge points.
Another disadvantage of weather radar is that due to attenuation,
it may not see the "storm behind the storm" or may understate its
intensity. The WX-500 is not subject to attenuation. With the WX-
500, electrical discharges are mapped throughout the storm area.
The size of the cluster of discharge points detected by your WX-
500 indicates the size of the storm area. The speed with which the
discharge points appear indicate the intensity of the storm regardless
of the size of the cluster. The more intense the storm, the faster the
discharge points reappear.
2-4 Stormscope WX-500 User's Guide
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