Disneyland during Half Marathon Weekend?

We live in SoCal, but only get to Disney once a year. This year we are going on September 4th for my son’s birthday. That weekend is a half marathon weekend. What impact can I expect? It says there is a Marathon starting at 5:30 a.m. that morning. How much time should give ourselves in driving down from LA to get there?

They’ll have road closures in the area starting very early. You can google a few days before the race to see what is closed. This is from Tink weekend, which will give you an idea. http://www.laughingplace.com/w/news/2015/05/05/road-closures-announced-for-tinker-bell-half-marathon-weekend/ the program showing race courses http://as1.wdpromedia.com/media/rundisney/pdf/disneyland-half-marathon/2015/2015_DLHM_Program_Online.pdf