About Traffic Predict

Traffic Predict shows how fast freeways in California and the Twin Cities are moving right now, how they're likely to move over the next few hours, and how they moved at any time in the past.

Where the data comes from

Caltrans has more than 10,000 detector stations embedded in freeway lanes across California, and MnDOT has nearly 2,000 on the Twin Cities freeways. Every 5 minutes Traffic Predict downloads the latest readings (for California from Caltrans' Performance Measurement System) and colors each stretch of freeway by its average speed. Incidents come from the California Highway Patrol and, in Ohio, from ODOT's OHGO service, which also reports work zones and sudden slowdowns.

More states are on the way as their transportation departments' free data feeds are added.

Reading the map

• Colors show speed: green is over 60 mph, blue 45–60, yellow 30–44, orange 15–29, and red is under 15 mph. Gray means that sensor didn't report.
• Each direction has its own line. Zoom in and the two sides of the freeway separate, just like the real lanes: northbound on the east side, southbound on the west.
• Tap or hover any stretch to see its speed and what's normal there at this time.

Now & ahead

Drag the slider to see predicted traffic up to four hours from now. The forecast starts from what the sensors report right now and blends toward what usually happens at that time of the week. A slowdown that's out of the ordinary is assumed to clear up gradually over about an hour.

Switch to Compared to usual to spot trouble: instead of raw speed, each stretch is colored by how its speed compares with a normal day at the same time.

Replay

Pick any day and hour and press play to watch the actual traffic, in 5-minute steps, the way it happened. Use Week ◀ ▶ to compare the same hour on other weeks.

Typical

Pick a day of the week and an hour to see what traffic normally looks like then, averaged over every week Traffic Predict has recorded. Planning Friday's drive? Check Friday, 5 pm.

The history behind forecasts and typical traffic grows every week, so they keep getting more accurate.

Coming next

California Highway Patrol incident reports on the map, so you can see why traffic is stopped.

Credits

Traffic data: Caltrans PeMS and the California Highway Patrol; MnDOT (Twin Cities freeways); Ohio DOT via OHGO (incidents, work zones and slowdowns). Map data © OpenStreetMap contributors, tiles by OpenFreeMap, map rendering by MapLibre.

Traffic Predict is an independent site and is not affiliated with Caltrans or the CHP. Speeds and forecasts are estimates. Never check the map while driving.