I remember the Helix actually came with a warning that it needed to be stored between certain temps (don't remember what the range was). If it got outside the range the uerathane would split from the resin and you'd end up with a 3 piece ball. Where the problem comes from is that bowling balls are made of different parts, all of which have different densities (coverstock, filler, core) which will expand and contract at different rates due to temperature. I know it sucks, but take the time to lug your stuff inside during the winter. Chances are, you'll be ok, but why take that chance with a $200 ball?
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The clock on the wall says 3 O'Clock...last call...for Alcohol!
"I love a martini -- but two at the most. Three I’m under the table; Four, I’m under the host." Dorothy Parker