Flashing red in all directions at an intersection

[bzakharin]

So I just encountered one of these on a signal somewhere in rural northeast PA. Took a while to figure out that's what it was, since I've never seen one before, and it's kind of hard to see the light displayed for cross traffic, so sat there waiting for the relatively heavy traffic on the cross street before figuring it out. I've heard of 4-way stop signs of course, but 4-way flashing reds don't give you any direct clue as to their existence. How common are these?

[vdeane]

New York has a few.

[roadman65]

They have them in Alabama and there used to be one in Yeehaw Junction, FL at the intersection of FL 60 and US 441.  In most cases the STOP signs are still supposed to say 4 Way or ALL WAY.

Maybe you missed those signs as the MUTCD requires signals alone cannot be sole traffic control devices when being used as beacons.

[bzakharin]

Perhaps it wasn't clear from my post, but these appeared to be regular traffic signals (with red, yellow, and green balls) that happened to be flashing red in all directions. It wasn't anything like those permanent double-flashing red or yellow beacons I encounter quite frequently. In any case, there did not appear to be any stop signs in any direction at any approach.

[corco]

Perhaps it wasn't clear from my post, but these appeared to be regular traffic signals (with red, yellow, and green balls) that happened to be flashing red in all directions. It wasn't anything like those permanent double-flashing red or yellow beacons I encounter quite frequently. In any case, there did not appear to be any stop signs in any direction at any approach.

Are you sure the power wasn't out?

[bzakharin]

Perhaps it wasn't clear from my post, but these appeared to be regular traffic signals (with red, yellow, and green balls) that happened to be flashing red in all directions. It wasn't anything like those permanent double-flashing red or yellow beacons I encounter quite frequently. In any case, there did not appear to be any stop signs in any direction at any approach.

Are you sure the power wasn't out?

Can't be 100 percent sure, but certainly there were no other signs of this. Why would that matter? Are traffic lights programmed to flash red when power is out? Or do you mean I didn't see the stop sign because the power was out? Since it was during the day, the latter is not the case.

[jeffandnicole]

Perhaps it wasn't clear from my post, but these appeared to be regular traffic signals (with red, yellow, and green balls) that happened to be flashing red in all directions. It wasn't anything like those permanent double-flashing red or yellow beacons I encounter quite frequently. In any case, there did not appear to be any stop signs in any direction at any approach.

Are you sure the power wasn't out?

Can't be 100 percent sure, but certainly there were no other signs of this. Why would that matter? Are traffic lights programmed to flash red when power is out? Or do you mean I didn't see the stop sign because the power was out? Since it was during the day, the latter is not the case.

Depending on the default, they can be made to flash yellow/red, or all red.  Sometimes it depends on the sight conditions - if it's too dangerous for the side street to get a good sight view of the main road, it may have been programmed to default to all red.

It could have also been a new signal which are set to flash for a few weeks for motorists to get adjusted to it.  Same thing though - defaulted to all red because of limited-sight conditions.

[Brandon]

So I just encountered one of these on a signal somewhere in rural northeast PA. Took a while to figure out that's what it was, since I've never seen one before, and it's kind of hard to see the light displayed for cross traffic, so sat there waiting for the relatively heavy traffic on the cross street before figuring it out. I've heard of 4-way stop signs of course, but 4-way flashing reds don't give you any direct clue as to their existence. How common are these?

Very common in some places if the signal isn't needed for lower traffic period such as the overnight hours.  In Michigan, it is not uncommon for rural or small town signals to default to flashing red or flashing red/yellow in the overnight hours.

[bzakharin]

Perhaps it wasn't clear from my post, but these appeared to be regular traffic signals (with red, yellow, and green balls) that happened to be flashing red in all directions. It wasn't anything like those permanent double-flashing red or yellow beacons I encounter quite frequently. In any case, there did not appear to be any stop signs in any direction at any approach.

Are you sure the power wasn't out?

Can't be 100 percent sure, but certainly there were no other signs of this. Why would that matter? Are traffic lights programmed to flash red when power is out? Or do you mean I didn't see the stop sign because the power was out? Since it was during the day, the latter is not the case.

Depending on the default, they can be made to flash yellow/red, or all red.  Sometimes it depends on the sight conditions - if it's too dangerous for the side street to get a good sight view of the main road, it may have been programmed to default to all red.

It could have also been a new signal which are set to flash for a few weeks for motorists to get adjusted to it.  Same thing though - defaulted to all red because of limited-sight conditions.

I've seen red/yellow and all yellow before, but not all red. Learn something new every day, I guess

[Big John]

Can also be used when traffic is loo light to warrant regular usage of the signals, such as at nights and/or weekends.

[freebrickproductions]

The intersection of Holmes Avenue and Woodson Street here in Huntsville is currently flashing red in all directions due to Holmes being closed for a bridge replacement. I've seen it happen at other intersections like the intersection California Street, Fraser Avenue, and Lowe Avenue, and the intersection of Whitesburg Drive, Franklin Street, and Marsheutz Avenue. I have a video of the signals at the latter intersection flashing.
Most of the time, however, the signals flash yellow for the main road and red for the side streets.

[roadman65]

California uses them all around.  Also Orlando uses it at Oakridge Road and Orange Blossom Trail. 

The latter is up for discussion with the Orange County Traffic Engineering as Orange Blossom Trail should flash yellow in flash mode as Oakridge Road is not as major of a road as OBT is.  Even in normal timing you have to wait two light changes in the early morning rush hour to cross Oakridge Road which has only a few cars cross OBT when you have to wait.  It is all political reasons for this one that I do not want to go in to, but nonetheless it flashes as four way stop street when in beacon mode.

[roadfro]

Perhaps it wasn't clear from my post, but these appeared to be regular traffic signals (with red, yellow, and green balls) that happened to be flashing red in all directions. It wasn't anything like those permanent double-flashing red or yellow beacons I encounter quite frequently. In any case, there did not appear to be any stop signs in any direction at any approach.

Are you sure the power wasn't out?

Can't be 100 percent sure, but certainly there were no other signs of this. Why would that matter? Are traffic lights programmed to flash red when power is out? Or do you mean I didn't see the stop sign because the power was out? Since it was during the day, the latter is not the case.

Depending on the default, they can be made to flash yellow/red, or all red.  Sometimes it depends on the sight conditions - if it's too dangerous for the side street to get a good sight view of the main road, it may have been programmed to default to all red.

It could have also been a new signal which are set to flash for a few weeks for motorists to get adjusted to it.  Same thing though - defaulted to all red because of limited-sight conditions.

I've seen red/yellow and all yellow before, but not all red. Learn something new every day, I guess

A signal should never be set to all-way yellow flash mode--that's a safety concern, so I hope you haven't really seen that.

Depending on the signal cabinet hardware and battery backups, the signal can continue to operate during power failure--for some types of signalized intersections (SPUIs, complex intersections, intersections near rail crossings), battery backup is either highly suggested or required. I once got to see inside a signal cabinet with a City of Sparks (NV) traffic engineer. For the basic 4-way/8-phase intersection we were at, he explained that the battery backup could keep the signal operating in regular mode for about an hour, followed by up to 2 (or was it 4?) hours in all-way red flash mode.

[M3019C LPS20]

When a signal controller loses its main power supply, a battery backup system (if present) kicks in, which temporarily provides additional juice. At a typical intersection, a small cabinet (rather narrow in appearance) contains this system. It is almost always next to the signal controller cabinet.

Normally, a signal controller (computerized) will only put itself into flash mode if the conflict monitor in the set-up detects an issue that cannot fix itself. Also, you could program a signal controller to activate flash mode at a particular time of the day. This is likely true for the set-up you saw in Pennsylvania.

[Roadrunner75]

A signal should never be set to all-way yellow flash mode--that's a safety concern, so I hope you haven't really seen that.

Please advise the studio that made "Cars".  The signal on flash in the town (Radiator Springs?) is on 4-way yellow flash, resulting in a "Hey..wait just a second here!" moment when I first saw the movie, which is probably why I belong on this forum...

[Brian556]

Quote from roadrunner75:

Please advise the studio that made "Cars".  The signal on flash in the town (Radiator Springs?) is on 4-way yellow flash, resulting in a "Hey..wait just a second here!" moment when I first saw the movie, which is probably why I belong on this forum...

This, along with the US 66 shield that said "ROUTE" in the state name area, are the two things that annoy me about this otherwise cool movie.

[dgolub]

I'm pretty sure I've seen it somewhere along the way, but they're rare in the New York area.  Most flashers here are yellow for one direction and red for the other.

[Big John]

IDOT has a policy if the signals go into flash mode, it is red for all sides.

[pianocello]

Can also be used when traffic is loo light to warrant regular usage of the signals, such as at nights and/or weekends.

Or when traffic is too light to warrant usage of the signals at all, like in Gary. Some of the many stoplight-turned-4-way stops in Gary have physical stop signs installed at the intersection, but many don't.

[agentsteel53]

Or when traffic is too light to warrant usage of the signals at all, like in Gary. Some of the many stoplight-turned-4-way stops in Gary have physical stop signs installed at the intersection, but many don't.

this being Gary, I bet the stoplights don't work and the signs have been reappropriated.  such is the case in East St. Louis.

[CJResotko]

Here are a few examples of traffic signals in all-red flash mode without any stop signs:
Ortonville, Michigan, at the intersection of Mill Street and South Street (scroll around to see it flash): https://www.google.com/maps/@42.8523167,-83.4451247,3a,75y,113.72h,78.53t/data=!3m6!1e1!3m4!1so8oMkNeUge1PHhO5SONb2Q!2e0!7i13312!8i6656
Denison, Texas:
Fannin Avenue and W Main Street: https://www.google.com/maps/@33.755515,-96.5415569,3a,75y,156.97h,110.12t/data=!3m6!1e1!3m4!1sh30x-UamsR4e0uvNCqP5Qw!2e0!7i13312!8i6656'
Mirick Avenue and W Main Street (you can see signs under the signal that say "4-way"): https://www.google.com/maps/@33.7555622,-96.5429682,3a,17.3y,265.33h,101.23t/data=!3m6!1e1!3m4!1s5G9SiYjE1bNrW775r4VRAA!2e0!7i13312!8i6656

[mrsman]

Here are a few examples of traffic signals in all-red flash mode without any stop signs:
Ortonville, Michigan, at the intersection of Mill Street and South Street (scroll around to see it flash): https://www.google.com/maps/@42.8523167,-83.4451247,3a,75y,113.72h,78.53t/data=!3m6!1e1!3m4!1so8oMkNeUge1PHhO5SONb2Q!2e0!7i13312!8i6656
Denison, Texas:
Fannin Avenue and W Main Street: https://www.google.com/maps/@33.755515,-96.5415569,3a,75y,156.97h,110.12t/data=!3m6!1e1!3m4!1sh30x-UamsR4e0uvNCqP5Qw!2e0!7i13312!8i6656'
Mirick Avenue and W Main Street (you can see signs under the signal that say "4-way"): https://www.google.com/maps/@33.7555622,-96.5429682,3a,17.3y,265.33h,101.23t/data=!3m6!1e1!3m4!1s5G9SiYjE1bNrW775r4VRAA!2e0!7i13312!8i6656

I've always wondered if a signal were to go on permanent flash mode, wouldn't it make sense to just put in stop signs and remove the signal.  Use the signal hardware and equipment at other intersections or simply just recycle the equipment.

In DC, there are many intersections in Capitol Hill that used to be regular signals but are now glorified 4-way stops.  The streets are closed to regular traffic, unless you are on Congressional staff, due to security concerns.  They will never have enough traffic to need signals again.

This is the closest that the Google car got to one:

https://www.google.com/maps/@38.8941829,-77.0058696,3a,75y,176.15h,79.48t/data=!3m6!1e1!3m4!1sJkzR9Wm94rJJvsSH7SsS6g!2e0!7i13312!8i6656

[lepidopteran]

At least once I saw a setup with flashing yellow on the main road, and flashing red on the sidestreet.  Typical, but with one additional twist.  There was a Left Turn Signal on the main road as well -- and that one flashed (circular) red.  One installation flashed alternately/wig-wag style, the other in sync.

Not sure, but I think I saw this done once with a service road; the signals facing the service road flashed red (and presumably, the cross street did too) while the main road flashed yellow as usual.  Don't remember the sync pattern, tho.

[roadman65]

Lakeland, FL has one at Ariana Street and Wabash Avenue, but its a 3 way stop.

Orlando has a few, and many when two major arterials meet at a broken signal.

[jp the roadgeek]

This one on CT 364 was put here to supplement the stop signs after a fatal accident about 40 years ago.

https://goo.gl/maps/L5qGUKKtUqu