Kevin Myatt is The Roanoke Times' weather columnist.

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What happens in August stays in August.

As we look at what appears to be developing in the upper-air pattern across North America, it looks as if the heat wave of 2007 will stay neatly confined within the month of August.

Computer forecast models are consistently latching onto what would be a major weather pattern shift beginning late next week.

It is a shift so large that we could go from the blazing August heat to a period of unseasonably cool weather to start September. For now, though, let's hedge our bets and just say that early September looks to be a lot closer to normal, devoid of record high temperatures.

That's what the last half of July was like. Roanoke did not go above 90 degrees for the last 12 days of that month, and the high was a weirdly cool 72 on two days in that stretch.

But then came August, when 22 of 24 days through Friday had highs at or above 90 degrees in Roanoke, three have reached or exceeded 100, and four others have reached either 98 or 99.

Though we've had a couple of days this week that haven't been so hot, thanks largely to some damp Atlantic Ocean air from the northeast, this weekend will be more akin to the rest of August. A high in the upper 90s to possibly 100 appears likely today.

The heat is from that same high-pressure system -- a huge dome of hot air in the atmosphere -- that has been meandering around the country all summer.

It started in the West early in the summer, and to the West it will return.

For days, long-range computer forecast models have been showing high pressure rebuilding over the West, returning heat to that area. This, in turn, leads to a southward buckle in the jet stream over the East, allowing cooler air to filter in from Canada.

Computer models are far from perfect in weather forecasting, but when they start showing something very similar day after day, pay attention. Even if the details and timing aren't exactly right, such consistency usually means the models are picking up on some major changes.

As a general rule, when one side of the country is unseasonably warm or cool, the other side is the opposite with equal intensity. It's like a seesaw -- the seesaw is high in the air on one side, it's on the ground on the other.

So we'll see to what degree the new jet stream pattern takes shape, whether it will be extremely hot in the West and extremely cool in the East, or more moderate.

Either way, it appears the torrid run of heat is near its end.

One cold front will move against the heat on Sunday, and this could chop a few degrees off the temperature next week. But highs will rise again, as they have after previous cold frontal passages this month, possibly into the 90s once more, before a stronger front moves in about Friday, the last day of August.

With our average high, low and overall temperature for the month all running 1-2 degrees ahead of the pace for records, the last question the August heat wave of 2007 has to settle is whether it can finish its quest to be the hottest month in our recorded weather history.

It's going to take more than just a few days with highs in the 80s and lows in the 60s to topple the averages of such a persistently hot month. I think this heat wave has too much momentum, and August will cross the tape as our hottest month on record.

I will let you know all about that next Saturday when August is history.