'Drought Makes More Drought': What it takes to break through a dry spell

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Friday, July 15, 2022
'Drought Makes More Drought': What it takes to break a drought
There's an old saying, drought begets drought, but why does drought make more drought?

RALEIGH, N.C. (WTVD) -- Last night I got a phone call from a viewer asking why the radar was showing rain over his area, but he wasn't seeing any at this house. It all has to do with our ongoing drought.

There's an old saying, drought begets drought. The reason those old weather sayings stick around is because there is some truth to them. But why does drought make more drought?

Well, part of it has to do with the dry ground. As the ground dries out, it creates dry air above the ground. The plants and dirt and soil are all trying to get any moisture they can, so they suck it out of the air creating a bubble of lower humidity. As systems with rain push into the region, that 'bubble' of dry air will actually absorb moisture before the raindrops ever make it to the ground.

Sometimes, you can actually see rain shafts falling out of clouds, but they just fade away as they get closer to the surface. These shafts are called 'Virga'. Virga is just rain that doesn't make it to the ground.

Another factor in the drought, especially in rural and farming areas, is the plant itself. Usually plants will give off moisture as they grow and that adds to the humidity in a region. During a drought, the plants will hold on to their moisture and that can also contribute to the dry air.

Finally, heavy rain doesn't always help either because if that ground is dry, and hard enough, most of the needed water may just run off into creeks and streams and never soaks into that hard ground.

The way to break a drought is to have several systems passing over with light to moderate rainfall. If you get lots of days with just a little rain, your humidity starts to go up. And if the air is humid, those rain drops can finally make it back into the ground. That rainfall really adds up over days and the drought simply goes away.

Over the past week we've seen a lot of these systems pass through, and the latest drought monitor (issued by the National Drought Mitigation Center at the University of Nebraska-Lincoln) shows improvement across the ABC11 viewing area.

Plus, we see a chance of rain every day in our 7-day forecast. Those continued passing showers should really start to add up and continue to make our drought fade away.

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