Bolting

Question of the Day: What does bolting spinach look like?
It is June 18, and here in Denver, my lettuce has been doing great! I have a carpet of green and red lettuce that seems to replace itself every time I pick it. The spinach has not been quite as productive, and I feel like, with temps rising into the 90s, its only a matter of time before everything goes to seed. I'm seeing some suspicious signs of bolting of the spinach . ..