Boltek NexStorm Lite - Manual (Page 20)

Lightning Detection Software, Version 1.0
Strike symbols tab
Use this dialog to configure the symbol generator, assigning strike symbols to be used for plotting different
categories of strikes on the map.
NexStorm can discriminate between two types of lightning, cloud to ground (CG) or intracloud/in cloud strokes
(IC). Additional filtering is done based on the polarity of the stroke and can be either positive or negative. The
NexStorm symbol generator allows you to visually discriminate between these four distinctive types of strikes
when they are plotted on the map.
Strike symbol configuration
To change a strike symbol for a specific type of strike, you must first select which type you want to change.
You do this by selecting the strike age (New Strike or Old strike button) and the strike classification
(radionbuttons -CG, -IC, +CG, +IC) Each combination can be configured to have a unique symbol setting.
(Note that the default configuration does not discriminate between the four possible stroke types.)
After selecting which strike you want to change you need to assign a symbol for it, you can browse through all
available symbols by clicking on the left and right buttons located at the bottom of the symbol preview area.
To change the size of symbols, press the up or down buttons located to the right of the symbol preview area.
If you need to assign a different color to a particular type of strike, click on the Color button to open the color
picker dialog.
The Equalize button is used to neutralize the visual discrimination of strikes by setting all symbols to be equal
as the currently selected strike category. This means that if you press this button, all categories of strikes will
use the same symbols for New strike and Old strike as the currently selected category.
Due to its long continuing current, a positive cloud to ground stroke (+CG) is considered to be one of the most
dangerous forms of lightning and is often the cause of lightning initiated fires and human deaths.
Studies show that many +CG strikes originate from the anvil at the top of the Cumulonimbus cloud which is
the type of cloud associated with thunderstorms. As the cloud tops due to atmospheric conditions generally
are lower at higher latitudes, the distance between the cloud top and the ground becomes shorter. This
shortened cloud to ground traveling distance creates more favorable conditions for a +CG discharge and is
why this type of strike is more likely to occur the farther north or south you are in the world. At southern
latitudes, storms with predominantly +CG discharges are likely to be severe with a potential of producing large
hail and tornadoes.
Edition: 5/L1
2007-09-02
© 2007 Astrogenic Systems Table of Contents Page 20