Kevin Myatt is The Roanoke Times' weather columnist.

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Your perception of what a "heat wave" is varies greatly depending on what part of the country you grew up in. But based on this area's long-term averages, we have entered another period that could legitimately be called a heat wave.

We're about halfway through the month of August, and on a pace to establish a record for average lowest temperature for the second month in a row -- if the sticky overnight lows continue. Our daily highs are also decidedly on the hot end of history, so far this month.

Through Monday morning, the average low temperature for the month of August at Roanoke Regional Airport has been 69.3 degrees. Sunday's low of 73 degrees tied Roanoke's record for warmest Aug. 14 low temperature.

Over the previous 56 years of record-keeping, dating to 1948, the average August low temperature for August was 64.1 degrees at the airport.

The warmest August average low on record is 68.06 in 1995, according to data from the Southeast Regional Climate Center.

Recall that in July, Roanoke's average low temperature was 69.5 degrees, a half-degree above the previous record for warmest average low in July and about 4 degrees above the long-term average.

July's daytime highs were a degree below average, but August's highs are also on a pace that could challenge records, should the warmth continue through the month. We've exceeded 90 on 8 of the first 14 days of the month, including three days at 94 and one at 95.

Through Monday, the average high temperature for the month of August is 89.8 degrees. The long-term average for the month is 85.3 degrees. If the month ended Monday, it would rank as the third highest August average high temperature on record, trailing only 1959 (90.61 degrees) and 1983 (89.9 degrees).

But that's just it: The month isn't over. And usually, but not always, it starts getting a bit cooler as we slide down the back end of August toward the start of meteorological fall on Sept. 1.

This weekend marked a significant turning point in the national weather scheme, though it came at a deadly cost. The first really fall-like cold front dived out of Canada, triggering severe weather from the Rockies eastward to New England as it collided with hot, humid air.

A tornado touched down in Wright, Wyoming, causing widespread devastation and killing two people. It also snowed in Wyoming's mountains after the front went by, the first widespread snow in that region in a few months.

This front, like so many before it, is struggling to move through our area, though it could be enough to cause a few more thunderstorms the next few days as it interacts with the hot, humid air in place.

Temperatures should also back off a bit by mid-week as the front will probably get a little south of us before stalling out. This would help trim back our average temperatures.

The weather map shows a series of high pressure areas lined up across Canada toward the Arctic circle, pushing cold fronts southward. The shoving match between Canada and the Caribbean, between the tundra and the tropics, has begun.

It's a battle over the next two weeks to see if the hot air can hold on long enough to rewrite our August record books -- more through persistent warmth than extreme heat -- or whether fall's cooler air will start winning enough battles to skew the averages downward.

My bet would be that we get enough cooler air and storm-spawning fronts in the upcoming days to keep this from being a record August, but not enough to keep it from being a warmer-than-average August.