This is the first time I have ridden through the winter in 40 years thanks to my fat-tire bike. I've hardened up enough during the winter that I am actually enjoying the colder than normal spring weather. It's fun when you get the layers right, what with all the high-tech clothing. Cool but not cold with warm toes and fingers. The only two days I've missed riding this month are what the weather service called blizzard conditions. I don't do blizzards, there are too many ways to get hurt.
When the humidity is low enough, it is not unusual to have 40 or even 50 degree temperature swings during the day. The warmer spring days often start off below freezing and it cools down fast after dark. The average last hard frost at 6000' is May 15, make that June 1 on the west and north parts of the city above 7000'. I have a lot of storage on my bikes so I can add and shed layers as needed during my rides.
All this riding has really improved my conditioning. I have more mileage so far this year than all of last year. I'm afraid, though, now that I've become acclimated to the cold, I will really suffer the first few times the temperature hits 90.
April last year... this year the flowers haven't come out yet.