Mother Nature finally turns up the heat

Highs in the upper 20s forecast to start the weekend

Here comes summer, part two.

August has been a chilly preview of fall so far, with temperatures dipping to the single digits some nights, and just one day when the high reached 27.

The average afternoon highs should be 26 in early August, but many times we’ve been lucky to break 20, with grey skies and brisk northwest winds. It keeps the smog down, but doesn’t do much for a day at the beach.

“It hasn’t been muscle shirt and tank top weather,” says David Phillips of Environment Canada.

Finally, there’s hope. An extended warm spell — not exactly hot, but at least in the top end of the 20s — is set to arrive this weekend, with lots of sun.

The forecast highs are 26 for Saturday, 27 Sunday and warming up to 30 by Wednesday. Ottawa, like the Toronto Blue Jays, is trying to make a last run at summer.

And Environment Canada’s latest long-range “model” calls for warmer-than-average temperatures all across Eastern Canada from now through September.

So far, the August records from the Ottawa weather office aren’t pretty.

In the first 15 days of the month, highs have been below average 13 times and above average just once, by a single degree.

It also rained on seven of those days. And nine days had winds gusting above 35 kilometres an hour, often from the north. Our prevailing summer winds are usually from the southwest.

Cyclists riding in Gatineau Park early Wednesday even reported (and photographed) what looked like snow on the roadside, though it may have been hail from the storms in the night. Either way, it hadn’t melted by lunchtime.

July had 111 cooling degree days in Ottawa — a measure of how hard air conditioners have to work. August has had just 15.7 cooling degree days in half a month, showing that air conditioning costs will be way down.

It’s a contrast with last summer, the warmest on record in Ontario, Phillips notes. “Last summer you had all those Bermuda highs pumping in moist warm air.”

Spring this year was a little slow to develop “and then July really teased us and made us think that summer was really here,” he said. July had 10 days of 30 degrees or more in Ottawa, and its average high of 27.9 was 3.5 degrees above August’s, with figures through Thursday.

August so far has ended that. Phillips says the jet stream, the high-altitude band of wind circling the planet, normally shifts to the north of us in summer and lets warm air flood in from the south.

This month it has maintained a position right overhead, which has prevented warm air from moving in. It hasn’t been spectacularly cold at any point, but “there’s been a feeling in the air that it’s more like September,” Phillips says.