This article is from the Bicycles FAQ, by Mike Iglesias with numerous contributions by others.
In the winter, the road is narrower. There are snow banks
on either side. Cars do not expect to see bicycles. There
are less hours of daylight, and the its harder to maintain
control of the bicycle. Be careful.
I don't worry about what legal rights I have on the road, I
simply worry about my life. I'd rather crash into a snow
bank for sure rather than take a chance of crashing into a
car. I haven't yet had a winter accident in 12 years. I've
intentionally driven into many snow banks.
Sometimes, during a storm, I get into places where I just
can't ride. It is sometimes necessary to carry the bicycle
across open fields. When this happens, I appreciate my
It takes a lot more energy to pedal. Grease gets thick, and
parts (the bicycle's and mine) don't seem to move as easily.
My traveling time increases about 30% in nice weather, and
can even double during a raging storm.
The wind seems to be always worse in winter. It's not
uncommon to have to pedal to go down hills.
Be careful on slushy days. Imagine an 8 inch snowfall
followed by rain. This produces heavy slush. If a car
rides quickly through deep slush, it may send a wave of the
slush at you. This stuff is heavy. When it hits you, it
really throws you off balance. Its roughly like getting a
10 lbs sack of rotten potatoes thrown at your back. This
stuff could even knock over a pedestrian.
Freezing rain is the worst. Oddly enough, I find it easier
to ride across a parking lot covered with wet smooth ice
than it is to walk across it. The only problem is that
sometimes the bicycle simply slides sideways out from under
you. I practice unicycle riding, and that may help my
balance. (Maybe not, but its fun anyway)
Beware of bridges that have metal grating. This stuff gets
real slippery when snow covered. One time, I slid, hit an
expansion joint, went over the handle bars, over the railing
of the bridge. I don't know how, but one arm reached out
and grabbed the railing. Kind of like being MacGyver.