Cold Weather Boosting

[Alpine TSi]

I was having some minor issues with my car yesterday that I am hoping are just weather related.

I couldn't slam the throttle down for an entire gear like I can in normal 70+ weather, what would happen is at about 5K rpm in 3rd I would be at about 18psi and then the car would just start missing really bad and then I would shift into fourth and it wouldn't go anywhere(at full throttle) for about 5 seconds, then it would go. I was doing fine with about 11.2-11.9 AFR's and no boost creep, so I wasn't running lean. However for giggles I decided to hit the peak/hold function on my AFC2 and the incoming MAF frequency was at 5200hz(straight value with nothing taken out by the GM MAF) at 5100rpm where I shifted out of third. Now I rarely see about 3200hz even at 25psi at the track so I am assuming that this was because the outside temp was about 35 degrees and the air was already so dense. Is this thinking correct or am entirely wrong? If I am right why would I miss so badly? Today with slightly cooler than normal temps I was fine all the way through third and fourth.

I probably should just turn the boost down at this time of year, but I really want to have as much fun with my car as I can, if it costs me my motor, so be it.

Thanks in advance.