Left-turner at a green light with the sun behind you
Saturday, 5:30 p.m., you are northbound on a four-lane arterial in Wichita at 35 mph in the right lane. The sun is low and directly behind you. Up ahead, 150 feet away, the signal is green and has been green since you first saw it. In the southbound left-turn lane sits a silver SUV with its left turn signal on, inching forward; behind it, a southbound sedan is approaching in the through lane at about 40 mph. A cyclist is on the sidewalk to your right near the corner. The pavement is dry; your bike stops from 35 mph in about 70 feet with a hard, skilled stop, and your reaction time is about one second. As you watch, the SUV's front wheels twitch and it creeps another foot forward.
1. Identify the primary hazard in the next four seconds and describe what your hands, eyes, and throttle do.
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Primary hazard: the left-crossing SUV. It is the classic motorcycle fatality configuration, and it is worse than usual because the sun is directly behind you - the driver is looking into low sun and you are a small single headlight inside that glare. The creep is the tell: the driver is not waiting for a clear gap so much as inching toward a decision, and drivers who have already committed often go regardless of what is coming.
Hands: two fingers covering the front brake lever, right foot over the pedal, throttle rolled off. Speed: shed 35 down to about 25 mph, so your reaction distance and stopping distance both shrink. Eyes: on the SUV's front wheels and the gap between the vehicles, not on the driver's face - a driver's eyes will lie to you, front wheels will not. Headlight: flash the high beam once or twice to break through the glare.
Pre-plan: at every moment, know where you would go if the SUV turns now. Do not fixate on the SUV and do not assume green means go. Note the sedan behind it, which may also not see you, and the cyclist on your right, who could enter the crosswalk.
2. Choose a lane position within your lane and defend it against the other two options.
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Right third of the right lane, with a margin off the curb - not hugging the gutter.
The SUV travels from your left-front toward your right as it completes the turn. Sitting in the left third places you closest to where the turning arc begins and leaves you nowhere to go when the SUV commits; you have already spent your escape space. The center is where the arc crosses your lane soonest and is also where oil drips collect at an intersection approach, which is a poor surface for hard braking.
The right third buys two things: more distance from the turner's arc, so the SUV must travel further and take longer before it is in your path, and a ready escape toward the right edge or the cross street if the turn happens anyway. It also keeps you visible to the southbound through traffic on a broader angle.
The trade-off is the cyclist and the right-turn traffic, which is why you do not drift into the gutter - you keep the right third of the lane while scanning the sidewalk and crosswalk. Lane position is a decision you re-make as the picture changes, not a setting.
3. The light turns yellow when you are exactly 150 feet from the limit line. Stop or continue, and show the arithmetic.
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Stop, but only if you commit instantly.
Reaction: 35 mph is about 51 feet per second, so one second of reaction covers 51 feet. Add the 70-foot hard stop: about 121 feet total. From 150 feet you have roughly 29 feet of margin - about half a second of hesitation, and no more.
That margin improves in your favor here because you should already be at about 25 mph from the left-turner hazard. At 25 mph, reaction is about 37 feet and the stop is roughly 36 feet, so total is about 73 feet from 150 - comfortable.
What tips the decision: the margin only exists if you act immediately. A half-hearted "maybe I will go" while the light is yellow is how riders end up braking hard mid-intersection. Check the mirror first for the sedan behind you, who may not expect a stop, then brake firmly and progressively.
The reverse rule: if you are within about a second of the line or already past it when the light changes, continue through steadily. Do not accelerate to beat a yellow, and never stop inside the intersection.