"Frozen" shifter

I just recently starting having problems with my shifter freezing when it’s around 20 degrees & colder. It’s a manual 5 speed. I’m able to move it from 1st to 2nd by really forcing it but it will not budge into any other gear until it’s sat and ran for at least 10-15 minutes. This just started happening as I was driving through Utah’s frigid -15 degrees a couple weeks ago. I first noticed it was hard to down shift as I was pulling into a town after I had been driving for a good 9 hours at that point. What could my problem be? it’s 2008 Chevy Cobalt SS 50,000 miles

Thank you

Check the clutch fluid level. If the fluid is low it could prevent the clutch from disengaging completely, in which case shifting will be difficult.

If the shifter can be moved easily with the engine off, the problem is the clutch, not the shifter.