Recently on two occasions after sitting in the cold my shifter jammed and the clutch pedel felt like very loose like it was disconnected. After a little while, it I got the shifter into gear and all was normal. This never happened before. What could cause this?

It sounds like the clutch master cylinder seals are getting hard in the cold and bypassing fluid. I would suggest a rebuild kit at this point, I would do both the master and slave cylinders.

Bench bleed it before installing it, see if Autozone has a loaner bleed kit or vacuum (hand pump) bleeder.

There may be air in the system. Check clutch master cylinder reservoir level. It's best to bleed the hydraulic clutch every two years, as a preventive maintenance measure. If you haven't been doing this, I would take it to Honda and get it done.