Smoke in the forecast

When did "smoke" become part of the weather forecast?
It started on Tuesday this week. It's because of the forest fires in the interior, and a heat wave in the Lower Mainland. All the smoke has moved and settled in over Vancouver.

And the forecast is for it to stick around all weekend.

It has turned the sky all grey, and the sun looks kind of orangey red. It's made visibility so bad you can't see the mountains. And it's the first time I've ever seen "smoke" as part of the forecast. It's all very eerie!