SPOKANE, Wash. — Every Thursday morning, the U.S. Drought Monitor is updated. The update on July 11 expanded Abnormally Dry conditions in Washington from 78 percent to 86 percent while keeping Moderate Drought and worse at 55 percent.
The Drought Monitor map is a collaborative effort between National Oceanic and Atmospheric Administration (NOAA), U.S. Department of Agriculture (USDA), National Drought Mitigation Center (NDMC), and Department of Commerce. They collect nationwide data on rainfall, soil moisture, snow pack, and other various reports to detail the dryness or drought across the U.S.
While the latest Drought Monitor is published each Thursday, the previous weeks data from Tuesday to Tuesday is used, giving those agencies two days to analyze the new information.
The Drought Monitor itself is made up of five categories to express the level of drought. From least to most extreme, those categories are Abnormally Dry (D0), Moderate Drought (D1), Severe Drought (D2), Extreme Drought (D3), and Exceptional Drought (D4).
Washington summers are normally the dry season, and as the ground and soil looses moisture, dry and drought conditions almost always worsen through the season to varying degrees. In 2019, a dry late spring coupled with a lower than average snowpack has resulted in early summer drought conditions over about half of the state.
May was very dry in western Washington, and June was dry statewide. Thus all of western Washington and parts of northern and northeastern Washington are reporting Moderate and Severe Drought conditions. Same goes for north Idaho. And as of the latest update, the Abnormally Dry, or a stage below drought, was expanded to include Spokane and more of central and eastern Washington.
Moving forward, July, August and September are historically and climatologically the driest months. Only 0.6 inches of rain is the normal for Spokane each month, and for Seattle, that ranges from 0.7 to 1.5 inches of rain per month.
So unless there's an uncharacteristic widespread rainstorm at some point this summer, the drought will only expand and worsen with each passing week.