FIRST PM TRAFFIC ALERT, 4:36 PM: Thanks to the texter who reported the 35th/Roxbury stoplight is in flashing-red mode. We just verified it; and via Twitter, SDOT says its engineers have been alerted.
5:10 PM: Just checked. Still flashing.
SECOND PM TRAFFIC ALERT, 5:22 PM: A crash has closed southbound 4th Avenue S. at Spokane:
UPDATE: SB 4th Ave S is closed at S Spokane St. Use alternate routes! Backup growing fast. pic.twitter.com/RdzhH7so53
— seattledot (@seattledot) February 4, 2016
Turns out this too has to do with a flashing traffic signal – resulting from crash damage, and causing big backups.