[time-nuts] Do ordinary clouds adversely affect GPS reception?

[Andy]

Having had DirecTV on the roof for a few years, and having experienced
regular significant signal loss events during heavy rain and snow (loss of
reception was a rather good predictor that "the skies were about to open
up" with rain), I can confirm that signal strength deteriorates noticeably
during these events.  They are in the same general frequency range.  There
are distinct frequencies where the loss is even more significant.

DirecTV probably tells you that this doesn't happen, but they are wrong;
but that's their salesmen speaking.  Experience shows that it's real.  When
it rains, I could watch the signal levels drop on their meters, then watch
the channel banks disappear.

If someone had reasonably good GPS reception, then the signal loss might be
small enough to go unnoticed by the majority of users.  If your friend's
reception was already near borderline, then it should be obvious that any
little bit can put it over the top.  I think your friend did not imagine
it.  I think the loss is more than a few dBs when it's raining, not
trivial.  It's probably small when it is just cloudy, but like I say, under
the right conditions even a small change can put it over the top.

Andy