Most of these replies of "Gee, didn't you notice the storm around you?" replies must not live in the midwest. Here, lightning can be caused by heat and not just by storms. Also, especially during tornado season, you can have two storm fronts converge and without warning have a lightning storm spring up.
One other note: Lightning usually gives a warning before it strikes. This warning is usually the hair on your body standing up. Once you see this you usually have a few seconds to move quickly away from that area. Transformers on electric poles will also start to build up a loud hum up to 30 seconds before lightning strikes them. This is due to the massive amounts of negative or positive electrons that are building up (never can remember which one is at the ground).
One other note: Lightning usually gives a warning before it strikes. This warning is usually the hair on your body standing up. Once you see this you usually have a few seconds to move quickly away from that area. Transformers on electric poles will also start to build up a loud hum up to 30 seconds before lightning strikes them. This is due to the massive amounts of negative or positive electrons that are building up (never can remember which one is at the ground).