Ever hydroplane in a car? How about on a bike?
My Triumph Daytona 675 SE test bike is fitted with Pirelli Supercorsas, and while they're great for track riding they aren't the ideal wet weather tire.
Riding home last week in the rain was pretty hairy because there was standing water everywhere. A couple times I felt the front and rear lose contact with the road. A spooky feeling no doubt!
If it happens to you just hold tight and don't panic. The grip will return and then you can lower your speed.