Severe drought is expanding over the D.C. area

A combination of extreme heat, relentless sunshine and an absence of rain is driving the D.C. area deeper into drought. Much of the region is considered in moderate to severe drought, according to the latest federal drought monitor.

The drought has come on quickly, meeting criteria for a “flash drought” because of its rapid onset. It began in June and has shown little sign of abating. It was the driest June on record in Virginia and also abnormally dry in neighboring states.

July has picked up where June left off. Thundershowers that swept through the region Wednesday night produced minimal rainfall, and most of the area has 3 to 4 inches less precipitation than normal so far this summer.

The drought has worsened because of a vicious feedback cycle in which hot sunshine dries out the ground and causes temperatures to rise. The rising temperatures then speed up evaporation, which dries out the ground even more.

The District is enduring its second-hottest summer on record so far, and Wednesday was the sixth consecutive day to reach at least 97 degrees, the second longest such streak on record.

Here’s how bad the drought is

The progression of the federal government’s drought monitor in recent weeks shows how drought has quickly expanded and intensified across the region.

Advertisement

Much of the area is now in moderate to severe drought, the second and third levels on a 1-to-5 scale.

While the intense heat has made the drought worse, its primary cause is the lack of rain. June and July are the region’s wettest months, but sunny skies have dominated.

The District has a rainfall deficit of 4.5 inches since June 1. Only 1.54 inches have fallen since then, third least on record. Baltimore and Dulles have received only 1.6 inches (eighth driest on record) and 1.75 inches (second driest on record), respectively, over the same period.

The lack of rainfall has coincided with the summer solstice period when the sun is most intense. As a result, vegetation is suffering, with lawns turning brown and trees and other vegetation lacking water.

An improved outlook for rain

Some good news: Substantial rain could fall Friday, especially along and east of Interstate 95, where an inch or more could fall. Amounts will decrease to the west.

Unfortunately, another round of excessively hot weather is predicted between Sunday and the middle of next week. Highs well into the 90s or even around 100 will quickly dry out the land surface again.

Advertisement

But after next week’s heat wave, a more promising weather pattern for rain could develop. The area is expected to sit between heat domes in the Southwest United States and western Atlantic Ocean, which will result in a southerly air flow.

While that will elevate humidity, it should also increase the potential for showers and thunderstorms.

If the remnants of a tropical storm or hurricane passed over the area, that would be the easiest way to dig out of the rainfall deficit. An active hurricane season is predicted, but there are no imminent signs of any storm that would turn into a big rainmaker for us.

ncG1vNJzZmivp6x7uK3SoaCnn6Sku7G70q1lnKedZMSmrdOhnKtnYmV%2FdXuPcGZqaV%2BZv7DBxqGrZq6Zp7SqusiaZKaZoq65orrDZpucZw%3D%3D