The fierce yellow thing is not the sun; it is the flash on my disposable camera, which I couldn't turn off. to the right of the glow is Mt. Rainier. The building below the glow is the headquarters of Amazon.com.
This is I-5 looking south from the Key Tower to I-90. Compare these pictures with the picture looking north from the Key tower. This is a major choke point in the Seattle transportation grid. These photos were taken mid-afternoon (2-3PM) on a weekday in August 2000. The evening backup is just beginning to form. On the far left are the I-90 NB collector-distributor lanes, carrying traffic from I 90 and Dearborn Street, and traffic wishing to exit at James and Madison Streets. Exiting the mainline the C/D is one lane wide but it immediately picks up lanes from I-90 and Dearborn. Approaching Harborview Hospital the C/D is four lanes wide. At the Yesler Street overpass (foreground) the far right lane exits to James Street as an exit-only lane, the next lane is an exit-only lane to Madison, the third lane is the through lane, and the left lane ends.
The second set of lanes is the northbound mainline. It is four lanes wide at this point, but it goes to two at the base of the building. The two right lanes are the through lanes. The third lane is an exit-only lane for Seneca Street. The line of cars in the left lane are headed onto the express lanes, which begin at this point. Unlike the I-90 express lanes, the I-5 express lanes are open to all vehicles, with certain exit ramps / lanes being designated HOV only. Drivers prefer the express lanes to avoide the Mercer onramp-to-520-offramp weave that occurs a few miles north.
The third set of lanes is the southbound mainline. At the bottom edge of the map is the movable barrier at the entrance / exit to the express lanes. In southbound operation, general traffic exiting the express lanes has to cross the HOV lane on the inside of the mainline to the two general lanes on the right. This causes backups in the express lanes in the morning and frequent accidents in the curve just north of I-90.
Note the overhead sign gantry is devoid of signs. I-5 at I-90 was originally also going to have ramps to the cancelled R.H. Thompson Expressway. This gantry may have been intended to hold signs for that.
The set of lanes on the right is the I-90 SB collector-distributor carrying traffic from James Street and I-90, and traffic headed to I-90 and Airport Way / Safeco Field. It has three lanes exiting from the mainline (including the onramp from Spring St.). It picks up a lane from James Street but it becomes an exit-only lane to Airport Way and I-90 westbound. I-90 eastbound exits to the left. The two middle lanes narrow to one and merge with the ramp from I-90 east to I-5 south.