If you're reluctant to wear cycling shorts in public, one thing that might be worth considering are lightweight 'cross-sport' type athletic pants to wear over your bike shorts.

REI makes some really nice ones, they don't have a chamois pad so you can slip them on over regular bike shorts, they're not too tight and not too loose, except for near the ankles where you want them to be a bit more form fitting. And they look perfectly acceptable in public, say if you want to duck into a store.

http://www.rei.com/product/47857870.htm?

I wear these all the time over my bike shorts when it's chilly out , instead of tights or leg warmers. They're lightweight enough I can even wear them when it's not very hot. Granted, for very hot weather this isn't a good solution, but it's worth considering when the weather turns cool again.

- Jo.