U.S. Drought: Weekly Report for October 4, 2022

According to the October 4, 2022, U.S. Drought Monitor, moderate to exceptional drought covers 44.0% of the United States including Puerto Rico, an increase from last week’s 42.7%. The worst drought categories (extreme to exceptional drought) increased from 10.5% last week to 11.5%. 

The upper-level circulation across the contiguous U.S. began with a strong upper-level ridge over the West and a trough over the East. Hurricane Ian was drawn toward the trough at the beginning of the week; Ian’s remnants became absorbed into the trough and slogged slowly across the East as the week progressed. Meanwhile, a strong Pacific low pressure system slammed into the western ridge then stalled out over the Rockies. As a result of these competing weather systems, the week ended up wetter than normal across the Rocky Mountains, the Florida peninsula, and the Carolinas to New Jersey, while the rest of the contiguous United States had little to no precipitation. 

Weekly temperatures averaged warmer than normal beneath the ridge from the West Coast to the Great Plains, and cooler than average to the east under the influence of the upper-level trough and remnants of Ian. Drought and abnormal dryness contracted in the Rockies, where Pacific moisture left above-normal precipitation, and across the Mid-Atlantic under Ian’s heavy, flooding rains. But drought or abnormal dryness expanded in parts of the Pacific Northwest, where dry conditions and dozens of large wildfires continued, in much of the southern and central Plains to Mississippi Valley, and across parts of the Great Lakes to Gulf of Mexico coast. Nationally, expansion exceeded contraction, with the nationwide moderate to exceptional drought area increasing this week.

Abnormal dryness and drought are currently affecting almost 200 million people across the United States including Puerto Rico—about 64.1% of the population.