60-70F - Shorts, short-sleeve jersey, thin socks
50-60F - Shorts, long-sleeve jersey, thin socks
40-50F - Shorts, leg warmers, short-sleeve base layer, long-sleeve jersey, thin socks
30-40F - Shorts, tights, long-sleeve base layer, short-sleeve jersey, jacket, thick socks
10-30F - Shorts, tights, long-sleeve base layer, long-sleeve jersey, jacket, thick socks
<10F? - The trainer.