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by stevbov 1652 days ago
This is for California, not sure about other states:

Note that whether you have a solid green or a green arrow matters. A solid green means you can turn left, but you might have cross traffic. A green arrow means you're protected and as long as other people are obeying traffic signals, you shouldn't run into other people.

Lots of drivers don't understand this.

Lots of drivers also don't understand a red right arrow (as opposed to a red solid circle) means you cannot turn right on red. Most "no right on red" intersections have both the arrow and a sign (and many drivers ignore both).

7 comments

I've always thought the differences between the solid light and arrow was too minor for the average driver. I mean, look at the skills of the average driver.

In Washington state unprotected lefts weren't legal maneuvers for quite a while. They were introduced gradually starting at intersections where it would be a traffic benefit, for signaling the state adopted a blinking yellow arrow that then goes solid to signify the 'almost over' meaning of a typical yellow light.

One thing common in Texas is red light + green arrow to indicate a protected left/right turn. I suspect it's a lot easier to parse quickly for most people than green circle vs green arrow.
Is it? I see people sitting stopped at green arrows all the time because the red stop light takes priority in their mind. Presenting clearly contradictory signals at the same time can't be the best option.
Yeah honestly I'm not sure how would I take that. Maybe expect it to be a malfunctioning light? When presented with both 'stop' and 'go' you can bet I'm not going unless I explicitly verify that nothing is coming.
Really? The grandparent says it's common in Texas, but in my experience it's pretty common in all of the US (at least in urban and suburban areas), and shouldn't be surprising or odd to anyone who's learned to drive in the US or has been driving here more than a few months.

But I agree with you that you should verify that no one is coming in that case; that's sound advice for most all situations, really.

It may be a kneejerk reaction combined with me being very rurally located for work for these past 4 years, I think there are 3 traffic lights within a 45 minute drive and none of them will show red and green at the same time except in separate lanes when straight is red and left has a green.
The protected left should be the middle yellow with an associated cutout for the left arrow inside the light, with the normal through yellow turning on both the green and yellow left turn arrow, but likely way too many years of convention to make the change.
Are you referring to the traffic signals that have five options? That is, going clockwise starting at bottom left: green arrow, yellow arrow, standard red light, standard yellow light, standard green light

https://i.ytimg.com/vi/8MXdKQHddMk/maxresdefault.jpg

> a red right arrow ... means you cannot turn right on red

This varies a lot by state. Several allow turning (after a stop) on a red arrow. Some even allow turning left on a red arrow, if it's onto a one-way street.

https://driversprep.com/red-arrows-permit-practice-test/

That's seems unnecessarily confusing. Why even bother with the red arrow at all then? I guess it could be useful in cases where the straight-through traffic is green, but you want right-turning traffic to stop before turning, but is that common? Or even a useful thing? Like, I feel like if you've set things up that way, maybe the intersection is just designed poorly.
It is definitely confusing. In Washington state, right red arrow does not prohibit turning on red. I learned this after people started beeping at me to go at such an intersection. And yes, that intersection (Queen Anne and Mercer in Seattle) is confusing and poorly designed.
I don't think I've seen many intersections with red arrows unless there is a dedicated turn lane, where green yellow and red are all arrows. If it's a right turn in a right on red jurisdiction, without a sign expressing no right on red, why would red arrow be different than red circle?
MA allows right on red arrow after stop (absent a sign to the contrary). There are intersections where right on red is prohibited to protect a pedestrian walk phase that’s aligned with the green for straight ahead traffic.
> A green arrow means you're protected and as long as other people are obeying traffic signals, you shouldn't run into other people.

> Lots of drivers don't understand this.

This is logical. But, I've seen firsthand in Quebec (the city of Sherbrooke) where that's not the case. A driver may have a green arrow at the SAME TIME that a pedestrian has a walk signal. And in St. Thomas USVI I've seen opposing traffic have conflicting signals too (green arrow at same time oncoming traffic has green to go straight!)

I've lived in multiple states including California, and this is the first I've heard of red right turn arrows meaning no right on red. Good to know.

I believe I've also seen red right turn arrows in Pennsylvania, but they don't have any special meaning there. But I couldn't say for sure.

Huh, interesting. I've also lived in multiple states including California, and I've always understood a right turn arrow to mean no turn on red.

I wonder where the driver education here is breaking down.

Learned to drive (a long time ago) in PA and now live in CO. You’re right it’s all weird.

In PA, red arrow is just a regular red light that happens to be in a turn-only lane. All laws are the same as normal red light, the lane marking restrict your movement.

In CO, red arrow means stop and no turn on red regardless of lane markings.

Just about all traffic control laws are standardized federally except lights. That feels like the most important one to reduce confusion.

> Lots of drivers don't understand this.

Not sure I believe this. Obviously it's a fuzzy statement but I don't think I've ever once in my life seen someone blatantly ignore oncoming traffic due to having an unprotected left signal.

Any one driver's experience is necessarily extremely limited, a tiny fraction of a fraction of a fraction of all miles driven or traffic lights stopped at. You not having seen that happen should not be expected to be representative at all.

I have seen that happen, though fortunately there was enough time for both drivers to avoid a crash.

> Note that whether you have a solid green or a green arrow matters. A solid green means you can turn left, but you might have cross traffic. A green arrow means you're protected and as long as other people are obeying traffic signals, you shouldn't run into other people.

This is the same in the southeast, and I assume the rest of the US.

Recently "flashing yellow" [1,2,3] has been introduced to mean left turns must yield to right of way traffic. These are gradually replacing solid green signals.

[1] https://www.txdot.gov/driver/signs-and-signals/flashing-yell...

[2] https://durhamnc.gov/1140/Flashing-Left-Turn-Arrow-Informati...

[3] https://www.penndot.gov/TravelInPA/TrafficSignalsManagement/... (PDF)

This is confusing, generally a blinking yellow when going straight means slow down but you have right of way. A blinking left yellow would be different from a normal blinking yellow.
Yeah, it should probably be a blinking red arrow in order to be consistent. I'm sure some committee decided that wasn't different enough from normal red arrow
isn't flashing red a fail-safe triggered when the light controls fail that should be treated as a stop sign?

In practice that might work, but it's also a conflicting signal.

Blinking red would be a stop and proceed when safe sign. There’s no reason for each car to stop for a lot of these unprotected left turns.
This varies somewhat based on locality. In Oregon, for example, there is no special significance to a red right turn arrow. If a right turn on red is not permitted, there will be a sign.