U.S. Drought: Weekly Report for December 6, 2022

According to the December 6, 2022 U.S. Drought Monitor, moderate to exceptional drought covers 46.4% of the United States including Puerto Rico, a decrease from last week’s 48.1%. The worst drought categories (extreme to exceptional drought) decreased from 10.9% last week to 10.4%.

A series of fast-moving Pacific weather systems moved across the contiguous U.S. during this U.S. Drought Monitor week (November 30-December 6). They moved in an intense westerly flow that was created between a strong low pressure trough over central Canada and a high pressure ridge over the Gulf of Mexico. Their fronts and surface low pressure systems spread rain and snow across parts of the West and northern Plains. They tapped Gulf of Mexico moisture, drenching the Southeast and spreading rain along the East Coast. The precipitation was heavy enough to give large parts of the West, much of the Southeast, and parts of the Midwest and Northeast a wetter-than-normal week. 

Most of the Plains to Mississippi Valley, Great Lakes, and Florida were drier than normal. Temperatures were warmer than normal beneath the ridge along the Gulf Coast, in the Southwest, and much of the Northeast. The fronts and surface lows gave the northern states, from Washington and Oregon to Wisconsin, a cooler-than-normal week. 

Drought and abnormal dryness contracted across parts of the West, in northern Georgia and Alabama, and in the Tennessee and Ohio Valleys. Drought or abnormal dryness expanded or intensified in a few parts of the Plains, Upper Midwest, Southeast, and Hawaii. 

Nationally, contraction exceeded expansion, with the nationwide moderate to exceptional drought area decreasing this week. Abnormal dryness and drought are currently affecting over 196 million people across the United States including Puerto Rico—about 63.1% of the population.