http://www.nbcsandiego.com/news/local/Strange-Sound-Reported-San-Diego-Coastline-Mystery-Sound-160873565.html?dr
The mysterious sensation was described by some people
as sounding like a door slamming while others said it
was strong enough to rattle windows.
A check of the U.S. Geological Survey website showed
no earthquake activity.
NBC 7 San Diego's Dagmar Midcap was in Del Mar at the
time and described it as a "Sonic 'rumble'" She
tweeted, "according to my contacts at USGS, not
seismic but rather sonic."
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Hi Mary Anna,
As you may well know I live in San
Diego.
San Diego is a very highly populated
military town. ( Predominately Navy, Marine stations
through out the county of San Diego)
I live in the southern part of San Diego County near
the Mexico border, Coronado Island is within 15 minutes
and Imperial Beach is 10 minutes from my residence.
We experience alot of Helicopter and Fighter Jet
noise daily so when these events took place ( I can now
recollect twice in the last 10 days) that this unusual
noise has infact happened. I shrugged it off and JET
noise.
What is causing the noise I do not know but it did
infact happen.
God Bless
ybic,
Steven