People can tell themselves whatever they want in order to feel better, but Tom Brady doesn't struggle in the rain. Never has. I've watched him for 20 years, and he had some of his best games in inclement weather.
I wouldn't expect Dak to have more than 200 passing yards in this game. Not just due to the elite secondary he will be playing against, but the matchups up front don't favor the Cowboys. Biadasz is a liability, and there's not a better interior pass rush in the league than the one you will be facing on Sunday. Whether it's Christian Barmore, Judon kicking inside, or the occasional A gap blitz by Uche or Hightower, the Patriots will be in Dak's face all night.
Kamara had 89 yards on the ground, by the way, and averaged only 3.7 yards per carry. This is exactly what I mean when I talk about being fooled by average yards allowed per game. Teams are only averaging 3.8 yards per carry against us, but they are forced to run the ball a lot because they have no success against our secondary. So you may very well put up 150 rushing yards, but you will have to run the ball 35-40 times to do so, and it won't help you score a lot of points when your passing game gets shut down. You're not going to be able to run at will on this defense in the red zone.