Due to the actual wheater here in AUSTRIA we have temperature differences up to nearly 20 degrees Celsius from the early morning to the late afternoon of a day. Today I started my 60 km (37 mi) ride to work at -2 degree Celsius (28,4 F) an will return in the early evening at about 15 degree Celsius (59 F). What is your personal temperature limit for a ride?
Depends on what gear you have and what quality it is. My Bering textile jacket can be comfortably worn with a thin base layer and a T shirt down to about 0 degrees C here in the south of England but with my previous Triumph jacket I would have needed more layers or my Keis heated bodywarmer! Heated grips are essential (Heated seat is nice too!) Temperature won't vary that much in a day here - probably the most it will change this week is -1 to 7 degrees C.
Don't need to ride anymore to go at work, but the years I had to do that the only limit was ice on the road. Now over 50 I admit I'd be tempted around 0°C to take the car