Kevin Myatt is The Roanoke Times' weather columnist.

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Like a football team that keeps running the fullback up the middle, the polar region has kept sending cold fronts southward into the muggy subtropical high pressure area parked over the Gulf of Mexico and Atlantic Ocean.

The subtropical defensive line keeps stopping the cold front.

But sometimes, the fullback breaks through the line for a big gain. That may be about to happen by early next week.

Things look promising to finally get a cold front well to the south of our region, maybe all the way to the Gulf of Mexico, by Monday.

This is a significant development, if it pans out -- autumn's first touchdown of the year.

Every front since June that has tried to do this has stalled in Virginia or in the Carolinas. The result has been that any relief we get is brief, the humidity never really leaves, and we get days of off-and-on, here-and-there thunderstorms.

Monday and Tuesday was the latest effort at getting a front through. We had two days of thunderstorms -- some with damaging winds and hail -- then a slight retreat from the heat on Wednesday. But the heat and humidity will be returning the next couple of days as the front gets flung back to the north as a warm front.

A front is simply a boundary between markedly different air masses. It's all about which air mass is on the move that distinguishes a cold front from a warm front -- or a stationary front, if neither is moving much. The same boundary that is known as a cold front when cool air is pushing south becomes a stationary front when it stalls, then becomes a warm front when the sultry air from the south begins advancing north.

So that's what happening now -- what was once a cold front and then a stationary front has become a warm front, and the heat and humidity will return.

Cold fronts (really, they should be called "cool fronts" or maybe "not-as-warm fronts" this time of year) are typically pushed southward by high pressure areas in Canada. So it's a shoving match between the Canadian high and the subtropical high to see how far south the front will get. So far, the subtropical high has been winning every time.

But this time, the cold front will get an extra boost by a feature more typical for late fall or winter than for August. A strong low pressure system will wind up near the Great Lakes in southeastern Canada. The counterclockwise flow around this tightening low will help sling the cold front around, well to the east and south.

If this is fact how things develop, we could see some truly mild days in the early to middle part of next week. Highs may struggle to reach 80, lows may dip into the 50s. The oppresive humidity will also be pushed away, too, really the first time that would have happened for more than a single day since sometime in May or early June.

But this has yet to actually happen. There's always a bit of skepticism among forecasters when the pattern looks to favor something that hasn't occurred in weeks. There's still a chance that this front will get tripped up on the line of scrimmage like those before it, and that we'll be wallering in stormy, sultry slop again for a few days.

That's not what I expect this time. But to get to the cooler, drier weather, we may have to go through some turbulence first, in the form of strong thunderstorms, with Sunday being the day of highest risk. Severe weather will be a threat over a wide area of the eastern U.S. with a vigorous cold front plowing into hot, humid air.

The fullback may get bounced around at the line, even if he breaks through.