Here in NY they've started replacing traffic light bulbs with LEDs.
They're certainly bright enough (obviously it's a cluster, not just one
LED), and they have several advantages-- longer life, they tend to fade
a bit with time rather than simply fail, and they won't all fail at the
same time which is what obviously happens with one regular bulb.

Since the outside temperature in NY can reach close to a hundred
degrees in the summer daytime, obviously some LEDs work just fine at
higher temperatures.

Shaun Eli
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