A gravity surge is a like a specific area that is full of magnetic forces. When one who is not immune to such surges, they will immediately be taken over by the power allowing them to trip, stumble, fall or even slid.
When one is overexposed to gravity surges (though they may not be able to help that they are) they also become what some call, a spaz.
-- A method of distancing oneself from embarrassing actions such as dropping items, falling, spilling things, etc.
-- A way to divert the aggrieved party who has become soiled by your actions.
Daphne: Thanks for spilling your wine all over me!
Jill: Sorry, hon. It was a gravity surge.
Bill: Yo, toss me the remote, bro.
(falls 5 feet short)
Fred: Sorry, dude. Gravity surge.