Bay Area Traffic Trends

👆 Click any freeway to move the ○ and inspect that spot

Click a freeway on the map

Through the day

Typical speed over 24 hours (or a whole week). Click the graph to set the map time.

one line per year

This time of week, over the years

Window

Week at a glance

Every day & hour for the selected years. Click a cell to jump the map there.

Click a freeway on the map

Where & when congestion forms

Distance along the freeway (vertical) against time of day (horizontal) for the selected day and years. Slow zones growing and shrinking are bottlenecks and their queues.

Hours of congestion, over time

Congested = below mph

Best time to leave

Pick two points on the same freeway: click the map for the start (A), then press “Pick B” and click the end.

A: — B: —

Commute asymmetry

For every freeway location, how much slower than free-flow is each direction in the morning (12a–12p) and in the evening (12p–12a)? That slow-down is the "area above the curve" (mph·hours) on the Point graph. The map recolors each location by how lopsided the two directions are. Uses the selected day(s) and years; the time slider doesn't matter here.

Measure magnitude only (ignore which direction)

Click a freeway on the map

Most lopsided spots

Click one to go there. (One per stretch of freeway.)

Compare with another year

Pick a year to compare the selected years against. The map then shows the change in speed at the chosen day and time (green = faster now, red = slower), and the other graphs add a dashed line for the comparison year. Choose “nothing” to switch it off.

Compare to

Share of freeway that is congested

Region through the day

Share of all sensors below the congestion threshold for the selected day (threshold set on the Corridor tab).

Slowest spots right now

At the map’s selected day & time (one per freeway direction).