Watch the local weather program and keep an eye on the weather from outside look for anvil headed clouds with updrafts. Tune a portable radio onto AM low end of the band or to a part were you can only hear hiss .
When lighting strikes it gives off radio waves thus giving a crackle. You can normally pick this crackle up before you even see the storm. The cackle is called voice print also called sferics.
Lightning check for the U.K
http://www.weatherimages.org/data/imag394.html
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