Had pretty much the same thing happen to me last year. Decided to tackle my roof on a weekend that turned out colder than expected (thanks, weather forecast...), and ended up cracking a few shingles without even noticing. Come springtime, I had these weird lifted edges and thought I'd nailed wrong or something. Turns out shingles get brittle when it's cold—who knew roofing had a temperature sweet spot? Live and learn, I guess.
Yeah, cold weather roofing can be sneaky like that. A couple winters ago, I helped my brother redo his roof—figured we'd save some cash doing it ourselves. Temps dropped way lower than forecasted (typical...), and we ended up cracking shingles left and right without realizing it. Come spring, same deal: weird lifted edges and random loose shingles. Learned the hard way that shingles have their own comfort zone. Definitely a lesson you only need once, haha.
