It will be cooler in Seattle, possibly by 30 degrees. It's been in the mid-80s in Arizona for the past couple of weeks. There are other hurdles. The bright blue sky that proved so hellish in Arizona will be replaced by a sky as likely to be cloudy as sunny. If it's sufficiently cloudy to threaten rain, there also is a roof as likely to be closed as opened in April.
Baseball is all about making adjustments.
It's safe to say that Ichiro, the first Japanese position player to make it to the major leagues, has more adjusting to do than almost anyone before him. The first game after leaving Arizona proved to be a worst-case scenario for the Mariners. They got great pitching, didn't hit and lost 2-0. Just the scenario a team that is going to struggle for offense doesn't need. Starter Aaron Sele gave up just one hit, but it was an RBI double to Marvin Benard in the third inning.