Other than spraying at a lower pressure I don't see any problems.
You might not get an even coat though... I know there are special low pressure spray paints but I believe they're designed to be used with a special spray cap to get an even coating. Play it safe and wait for at least -5 before painting.
When you do paint try to keep the paint a bit closer than you normally would (eg. instead of spraying 12" away spray closer like 6-8" away). I'm not sure how temperature will affect the spray in the cold so the less distance it has to travel in the cold air the better it probably is.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE