Traffic on I-15 northbound was stopped near the California-Nevada stateline on August 29, 2025, due to a fiery crash involving two vehicles. One person was critically injured, requiring an airship for medical evacuation. The crash caused major congestion for miles as emergency crews were on the scene managing the incident and blocking lanes.
No other specific stoppages on different I- highways today (August 30, 2025) were found in the search results. If the question is about I-15 specifically, this is the main confirmed incident causing traffic stoppage. For other I- highways, there were no reported total stoppages but some delays and lane restrictions due to queues or roadwork.