It was pouring rain during the game. Hasn’t anyone worn leather gloves in the rain? They get wet, soggy, and they STRETCH. When the leather in the ball stretches, the pressure goes down!
Yes indeed. But what about the neoprene bladder that is within the outer leather skin? Is that affected by moisture?
Gas laws say 1.2 PSI from the air cooling 25°F.
Some example links of various types of treatment:
Slow cooling, dry:
http://www.wcsh6.com/story/news/local/2015/01/22/deflategate-patriots-football-pressure-inflated/22174475/
Quick cooling, via water, possibly incompletely cooled.
https://www.facebook.com/PathfinderRegionalVocationalTechnicalHighSchool?fref=nf
Slow cooling while wet: 1.8 PSI
http://www.youtube.com/watch?v=CxsXFX3tDpg&feature=youtube_gdata_player