Brake lever seizing up from cold I have perfectly ordinary standard-pull brake levers on my bike. When the temperature gets below 20F or so, the left-hand one seizes up, not wanting to pull, and not braking well if I force it. Once the temperature warms up a bit, it's fine.

Diagnosis? Cure? I'm pretty sure the actual brakes are fine, and the cable looks okay too.

(If there's a duplicate, feel free to kill this one; I looked but didn't find an exact symptom match.)
If the brakes are reluctant to move in both directions then it's mostly likely water in the lines. You may be able to get away with bringing the bike inside letting it dry out for a day or two and re-sealing the lines with grease.