Kevin Myatt is The Roanoke Times' weather columnist.

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@roanoke.com
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• We got graupel, but not on official record
• Moisture could get caught up in cold blast
• Forecast for Weather Journal: Partly print, with frequent Internet
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• Sprinkles or flurries possible Tuesday, but maybe something bigger for the weekend?
• For now, it looks like a quiet, mostly mild week ahead for SW Virginia
• Coldest morning of winter so far likely across much of Southwest Virginia; Tuesday precipitation looking doubtful
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The wet get wetter.

The dry get drier.

The dry get hotter.

The hot get drier.

Several times during the five years of Weather Journal, I have written about how it is possible to get in a vicious cycle where drought causes more drought, which causes more heat, which causes more drought.

Though we've had significant dry and hot spells during those previous years, we've never quite gotten onto the drought-heat treadmill.

We're there now.

Tuesday's fast-moving storms provided some welcome rain, but it wasn't nearly enough to break this drought.

The U.S. Drought Monitor may be calling it "abnormally dry," but when I'm walking across grass that crackles, I'm calling it a drought.

That crackling grass is part of the problem. Dried out vegetation, including trees, is not absorbing the same amount of solar radiation it would if it were healthy. That solar energy, instead, goes into heating the ground and heating the air.

There's not much water to evaporate on the ground, so the solar energy that would be used up in evaporation is also channeled into heating the ground and the air. The hot ground dries up what moisture remains faster, while the dry air inhibits significant rainfall from occurring that would replenish that ground moisture.

The hot, dry ground retains heat from previous days, making it easier for the temperature to rise the next day. Dry air heats faster than it would if it were choked with humidity from daily evaporation.

On and on it goes. The dryness makes it hot. The heat makes it dry.

Meanwhile, more than a dozen people in the Plains and Midwest have been killed by flooding, as the remnants of Tropical Storm Erin moved over regions that have gotten way, way too much rain over the past several months.

A hot high-pressure system is parked over the Southeast United States. The clockwise flow around the high is steering tropical systems around it, bringing the moisture northward into the central U.S. rather than close to us.

The high is also blocking cold fronts moving down from the north.

A cold front moved through this weekend, enabling one day of near-normal temperatures. Saturday's high of 87 snapped Roanoke's 19-day streak of 90-degree temperatures.

Then, the front reversed course as a warm front, and the next three days shot up over 90, including a high of 99 on Monday. That's 20 of the first 21 days of August at or above 90 as we head toward what will likely be our hottest August -- and possibly hottest month -- on record.

We can't get rid of our desert until the tundra or the tropics make a major move against it.

Both are blocked right now, and daily heat and dryness only serve to reinforce the high-pressure system in the way.

We're stuck. It will be another hot, mostly dry week. Don't be surprised to see another three-digit temperature reading by Friday.