The Washington State Department of Transportation is warning of major closures on several highways, including I-5, SR 18, and I-90, which are expected to cause traffic delays. The closures are part of ongoing construction projects, with some outlets reporting that the work is scheduled for a weekend, although the specific timing and affected roads may vary. The projects are likely to impact traffic in the Puget Sound area, with multiple roads, including I-405, SR 99, and SR 520, potentially being closed at some point.