U.S. Drought Monitor Update for April 6, 2021

According to the April 6, 2021, U.S. Drought Monitor, moderate to exceptional drought covers 37.6% of the United States including Puerto Rico, an increase from last week’s 36.7%. The worst drought categories (extreme to exceptional drought) increased from 15.6% last week to 16.9%. 

Atmospheric circulation consisted of three upper-level Pacific weather systems that moved across the contiguous United States in a generally westerly flow. They dragged surface fronts and low-pressure systems along with them. A weather system early in the week tapped Gulf of Mexico moisture to bring precipitation to much of the country from the Lower Mississippi Valley to New England, with above-normal amounts falling in some of these areas. However, most of the systems tracked along the U.S.-Canadian border, far from any moisture source, and so were mainly dry systems.  

At the end of the week, one system moved into the northern to central Rockies, dropping precipitation from remnants of Pacific moisture. As a result of this overall pattern, most of the contiguous United States had drier-than-normal weather for the week, with much of the West and Plains receiving no precipitation. The southern Plains to East Coast averaged cooler than normal for the week, while most of the West, Plains, and Great Lakes were warmer than normal.  

Drought and abnormal dryness expanded in the southern and northern Plains, and parts of the West and Great Lakes to Northeast, as well as southern Florida.  Most of the rain fell over areas that were drought-free, although some contraction of drought or abnormal dryness occurred in northwest Texas, Minnesota, and the Southeast. Expansion exceeded contraction, so the moderate to exceptional drought area expanded this week.

Abnormal dryness and drought are currently affecting over 154  million people across the United States including Puerto Rico—about 49.6% of the population.