What a difference some days make.

It's hard to believe we were basking in record warmth just a week or so ago.

Now the opposite has become our new reality, with the bottom falling out of the mercury.

That's led Toronto to extend its Extreme Cold Weather Alert for a second day.

The warnings are issued whenever temperatures fall below -15C without the wind chill. It allows the city to open additional shelter beds and use more resources to help the homeless.

We most often see more than just one by this point in the season.

"Usually we see cold weather alerts starting in late fall, early winter, so it's really late this year," confirms the city's Elaine Smyer.

The dangers of staying out too long in these conditions are both obvious and deadly.

"People are out in milder weather in winter and they don't think the cold weather's coming," Smyer notes. "When it hits they may not be prepared so they could suffer frostbite or hypothermia and worse, they could fall asleep and it could result in death."

If you see someone in distress in the cold, call the Street Helpline at ( 416) 392-3777.

But even those with homes and heat are hurting in this sudden reversal of temperature fortune.

Except for maybe one man CityNews spotted walking downtown with just a light shirt and no coat on. "I'm just across the street on the third floor there so I was hoping to sprint across and get out of the elements here," he confesses.

The good news is that after a frigid night where wind chill values could reach -18C - that's zero on the old scale - things will be back to normal by Wednesday.

The bad news is normal is only -2C.

To check the current conditions and the seven-day forecast, click here.

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