My advice: layer, layer, layer! Leg warmers in 25 degree weather sounds like a very bad idea. Usually, your lower body doesn't overheat the way that your upper body does, so you're better off overdressing your legs. Good trick if you don't want to buy long sleeve jerseys: baselayer underneath, short sleeve jersey, arm warmers over the sleeves of your base layer. When you dress to leave in the house, don't only think about how you're going to feel after the first half hour of your ride. Also think about if you'll be able to stay warm if you get stranded or have to fix a flat. That probably sounds like strange advice, but I have learned this the hard way
