I can't beat -38c (that is pain crazy) but when I lived up in Mass on the South Shore I had some pretty chilly single digit plus windchill (both wind and bike reoduced) commutes, then add in some rain or snow. I actually carried a spare 'cross tubular since it was easier to pop that on a clincher rim and get moving than it was to fix a flat.
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk