emergency traffic control request
(Future)
Special request to preempt the current traffic control strategy in effect at one or more signalized intersections or highway segments. For example, this flow can request all signals to red-flash, request a progression of traffic control preemptions along an emergency vehicle route, or request another special traffic control plan.
emergency traffic control response
(Future)
Status of the special traffic signal control strategy implemented in response to the emergency traffic control request.
high water warning_ud
(Future)
High water warning information sent from one center to another.