The last official hooray of summer! Many spend Labor Day weekend outside at the lake, next to their pools or on the golf course, but officials are warning Phoenicians to plan for extreme heat this holiday weekend.

After a nice stretch of fairly moderate temperatures, the weekend’s expected excessive heat will be the second in less than a week. A First Alert has been issued for extreme heat over portions of the holiday weekend and it is expected to be hot.  The Valley is expected to be under an excessive heat warning from 10 a.m. Saturday until 8 p.m. Monday.

Daily high temperatures are expected to reach to hit between 106 and 108 degrees daily through Tuesday, which will be a few degrees above normal.

As per the new city policy, the excessive heat warnings will shut down several hiking trails in Phoenix. Camelback Mountain’s Echo Canyon and Cholla trails and all Piestewa Peak trails are expected to be closed Saturday-Monday from 11 a.m. to 5 p.m.