Thunderstorms. Cloud-to-ground or cloud-to-cloud?

[jack.h...@gmail.com]

Thunderstorms on Friday evening gave more than 50 mms of rain, almost 10% of the average annual total for this dry area (rain shadow).

Perhaps I learned something that I really should have thought about before.

Some storm cells passed directly overhead (the flashes).  But the thunder was not heard for several seconds.  Assuming a speed of sound of approximately 340 metres/second, the interval between the flash and the thunder puts the distance at 2,000 metres or more.  Hence, it was likely to be cloud-to-cloud lightning.

Not just that.  The thunder was heard not as a loud bang but more of a rumble.  This makes sense, as horizontal lighting (horizontal being a term of convenience rather than strictly accurate) means that the sound generated by different parts of the flash reaches the listener at different times, resulting in a rumble rather than a crashing bang.

So might it be, in general terms, true to say that thunder heard as a bang is cloud-to-ground, but when heard as a rumble, more likely to be cloud-to-cloud?

Jack

[Metman2012]

I agree with you Jack, having come to the same conclusion not very long ago. Wisdom in old age?

Malcolm