Ghoward is right.
In Texas, lawnmower etiquette is going to be slightly different. In the middle of Summer, it gets real hot real early. So you should cut your neighbor some slack if he mows right after the sun comes up, because if he waits any later it's going to be miserable to mow the lawn.
When it's not so hot, I think it's appropriate to hold off until 9:30 or so on weekends.