A lot of time, it's just dumb luck.
Yesterday morning, the sky suddenly burst into color...As I was waiting to make my left turn into McDonald's for my early morning cuppa, I grabbed my little point & shoot from it's hiding place within my dashboard and shot off two pictures, figuring I'd get some more from a more scenic spot a half-mile up the road after I left the drive-thru. I couldn't have been in the drive-thru for more than 90 seconds...by the time I got back to this spot, the color was gone, the sky was a cold slate gray, and we never did see the sun....we had a low heavy overcast and drizzle all day. Total time of this colorful sunrise: Around 2 minutes from gray to gray.