PORTLAND MAX trains were running behind schedule Monday due to hot weather.
Temperatures above 90 degrees could cause safety issues on MAX trains running at high speeds. Trains were running up to 10 miles per hour slower than normal.
The overhead wire will sag in the extreme heat and the rails will expand, said Roberta Altstat, spokesperson for TriMet.
The slower speeds are necessary to not damage the wire and rails, Altstat said.
Riders should expect delays of up to 15 minutes.