Lately when i open my gas tank cap there is way more pressure then usual being expelled?
could this be from the hot weather and running premium gas?
Like i can feel the pressure push out when i open it, its weird?!

 

I get the same thing in the hot weather.
I would guess that due to the heat the preasure builds up more.

 

Yes, and yes. As the fuel heats up it expands and turns to vapour. That vapour is what comes out when you open the cap. Highly flammable too so no smoking . Your charcoal canister should vent some fumes but you will still get some pressure. When the gas cap pops off in your hand then start to get concerned about a blocked canister hose or something (unlikely) .
CoryM

 

If you have a blocked canister thats no problem, there is an emergency pressure relife valve ontop of your fuel tank so don't worry yes its from the excess heat, thing is GM designed the CC to purge regardles the same amount in cold & hot, they didn't account for temperature changes, either way, do what I did & eliminate it forever, remove your cat-back exhaust from the back & it'll vertually disapear, your milage will improve too