Most of the dreaded 405 freeway, a nightmare under normal conditions except in the wee hours, will be closed for 53 hours next weekend between the 10 freeway and the 101. The shutdown will begin late Friday evening, 7.15, and end at dawn on Monday, 7.18. Leave town or stay indoors or go into a coma, but forget driving to or from LAX on the 405 or going to the Valley for any reason, because north-south canyon traffic is going to be well beyond description.