Me three. This code comes on like friggin clockwork:

-After clearing codes and driving, get home, park in garage overnight.
-Starts up absolutely fine, idles gets out of neighborhood fine. Couple stops, engine warmed up some
-I could set my timer to it tomorrow, but 2.5 miles into it (engine warmed up, seems like as it goes into closed loop mode) measured 4.5 minutes into driving (light load driving):

-Check Engine comes on.

-Driving down the road with my reader, I can clear the code.
-Car drives fine the rest of the ride in - about 20 - 25 minutes mostly highway, with some stoplights and starts from a stop.
-Gets 26 MPG average just cruising

SOMETIMES: the light may or may not come on at lunch. Like you say, it seems that if it is cold outside, the odds are higher that it might come on at lunch, and I'll clear it again, and same thing.
SOMETIMES: It does not come on at lunch, or the drive home

Next day, same thing.

OCCASIONALLY: (Like today (50 deg outside at lunch) - Started it up, and the P0170 code came on, without tripping the CEL. It bucked a little, very little acceleration. Sure enough, checked the codes, and there it was - P0170. Cleared it, and it drove like a champ at lunch. Drove it home - fine., so

I replaced both O2 sensors while I had the head off (I looked at that rear one, and thought with the miles I would do it then. (I bought the car with a broken timing belt, so I don't have personal history)

New Plugs
Cleaned TB while it was off
Good overall performance
Replaced the cloth covered vacuum lines while the head was off
Have checked the rubber hoses for cracks - but admit I need to look again.

Two things need/want to do:

- Clean MAF and monitor
- There is a fitting under one of the valves under the intake that has a rubber elbow on it. Goes nowhere. Strage - I do not see a line that should go there, and I have looked at the vacuum routing and don't see a line that should go on it. It is one of the small square valves that is on the triangular plate, the one closest to the firewall