U.S. Drought Monitor Update for January 29, 2019

According to the January 29, 2019, U.S. Drought Monitor, moderate to exceptional drought covers 14.3% of the United States, a decrease from last week’s 17.1%. The worst drought categories (extreme to exceptional drought) decreased from 1.7% last week to 1.6%.

During the week, a low pressure system in the central Plains moved through the Great Lakes to Northeast. Once that system exited the country, a strong upper-level trough became established over the eastern contiguous United States with an upper-level ridge over the West. The trough funneled frigid arctic air into the country east of the Rockies, while the ridge kept most of the West drier and warmer than normal.

Weather systems moved over the ridge, brushing the Pacific Northwest with precipitation, before plunging into the eastern trough where they intensified and brought rain and snow to parts of the Plains to East Coast. As a result, the week was generally drier than normal across much of the West into the southern Plains, and wetter than normal in the northern Plains and most of the contiguous United States from the Mississippi River to East Coast.

Drought and abnormal dryness expanded across parts of the Pacific Northwest and southern Plains and parts of Hawaii where dry conditions worsened. Drought and abnormal dryness contracted in parts of southern Florida and southern Texas, where precipitation was above normal, and parts of the West where precipitation over the last 30 to 60 days warranted improvement.

Abnormal dryness and drought are currently affecting over 66 million people across the United States—about 21.4% of the country’s population.