Zero.
I'm not going to waste my time trying to explain on here about what a surge is or how it occurs. It's been done to death on numerous occasions. If you're that interested, try a search. Far more learned people than I have written it up.
As for my expirence (sic); you don't know me from Adam, and I certainly wouldn't profess to being a 'master', just a humble B1, but any schoolboy will tell you that low pressure cannot 'flow' to a high pressure area.
It's nice to see somebody wishing to expand their knowledge, but don't come here, rolling you eyes at someone you don't know. Save that for when you KNOW someone's spouting bolleux.
Alternatively, stick to what you know. Maybe VTS management and 'engineers' should do the same!