Kevin Myatt is The Roanoke Times' weather columnist.

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It seems odd seeing the massive wildfires in parts of Florida and south Georgia that we think of as being swampy.

Well, it ought to be swampy down there, but years of drier-than-normal conditions have left some of it parched.

The past few months have been particularly troubling for their rainfall needs.

The El Nino pattern of the past fall and early to midwinter typically delivers copious rainfall to the Southeast, but this year, other climatic factors helped redirect those wet storm systems to the central U.S. instead. As a result, the Great Plains area was delivered from the widespread drought it was suffering a year ago, as that region has been consistently bombarded with large rain and snow events since late fall.

Since El Nino weakened, the Southeast has had a couple of rainy storm systems, but otherwise has been dry with weather alternating between extreme warmth and extreme cold.

Drought is an insidious weather threat. It often seems to sneak up on us during day after day of beautifully sunny, dry weather tailor-made for outdoor activities.

Before you realize it, water sources dry up and vegetation dries out to the point where a spark that would typically go out under average humidity spreads into a raging inferno.

We've gone through our own periods of drought intermittently in recent years, with some large wildfires and reservoirs with lots of cracked, dried mud.

The year 2001 still ranks as Roanoke's lowest rainfall year on record with 24.94 inches, but very wet years in 2003 and 2004 helped get us out of that drought. Since then, we've tended to be a little drier than normal, but nothing extreme.

We flirted with drought in spring last year before the flooding deluge of June's last week pretty much removed us for the remainder of the year.

According to the National Drought Mitigation Center in Lincoln, Neb., which reviews a variety of data including recent rainfall, soil moisture and stream flow, Virginia is clear of drought at this time even though, here in Roanoke, eight of the past 10 months have been at least a half-inch below normal in precipitation.

However, almost all of the nation south of Virginia and west to the Mississippi River -- excluding central and eastern North Carolina -- is experiencing drought, rated as severe by the drought mitigation center in parts of Alabama, Georgia and Florida.

The drought mitigation center uses a couple of rather complicated indexes to determine when a region has reached drought, so I don't have an easily articulated definition of "drought" on hand for you.

The question that often hangs over us entering any warm season is whether that drought will spread to include our region.

Drought has a self-perpetuating nature to it. When a region is dry, there is less moisture for clouds or precipitation, so that dryness tends to become worse and cover a wider region. Vast areas of dry ground also tend to heat more in summer sun, which also helps worsen and expand the existing drought.

It usually takes major atmospheric pattern changes to break a region out of drought. It often doesn't happen gradually, but rather through a sudden shift to a period of heavy rainfall that, paradoxically, can cause major flooding as the hardened ground can't handle the runoff.

The past couple of days, we've had a strong high-pressure system over the Southeast bring us unseasonable heat and dry weather. This particular high is transient and will be pushed off the coast for the remainder of the week, but if something similar becomes the prevailing trend a little later in the season, the Southeast's drought could spread northward into our area.

There is no guarantee this will happen. Last year, the concern was that strong high pressure over the parched central U.S. would expand eastward and spread hot, dry weather. Other than a couple of short intervals last summer, that really didn't happen.

Although there is a chance of thunderstorms today, there is little indication our area will experience any kind of widespread, soaking rain in the next week or so.

Drop by drop that's not falling, we could slip toward drought.