According to the Drought Monitor report of the U.S. Department of Agriculture (USDA), major Hurricane Ian made landfall in southwestern Florida on September 28 and then reemerged offshore of the Atlantic coast, with another landfall near Georgetown, South Carolina two days later.
Excessive rainfall (more than 10 inches) caused widespread inland flooding throughout the central Florida Peninsula and heavy rainfall overspread the Carolinas, Mid-Atlantic, and central Appalachians. After a mid-level low pressure system tracked inland from the northeastern Pacific and became stationary over the interior West, heavy precipitation (1 to 3 inches) occurred across northern Idaho along with the north-central Rockies.
Therefore, improvements were made across much of the East and north-central Rockies. Conversely, a dry week resulted in an expansion of abnormal dryness (D0) and moderate drought (D1) along with intensifying drought conditions across much of the Great Plains, Mississippi Valley, and Midwest. D1 was added to parts of the Pacific Northwest.
In the Midwest, increasing short-term precipitation deficits, periods of above-normal temperatures, and rapidly declining soil moisture indicators support widespread 1-category degradations throughout a majority of Missouri and parts of Iowa.
30 to 60-day precipitation deficits resulted in an expansion of abnormal dryness (D0) across southwestern Wisconsin and moderate drought (D1) across northern Wisconsin. Based on 30 to 60-day SPIs and support from soil moisture indicators, a slight expansion of D0 and D1 was warranted for southern and eastern parts of Lower Michigan.
Meanwhile, across the Ohio River Valley and eastern Corn Belt, increasing 30-day precipitation deficits led to a larger spatial coverage of D0. D1 was expanded in western Kentucky with the addition of severe drought (D2) in the lower Ohio River Valley, consistent with impact reports such as increasing wildfire activity and the requirement of dredging operations along the Ohio River between Paducah and Cairo.
Large precipitation deficits dating back 120 days support a large expansion of D0-D2 coverage throughout Minnesota. Lake Minnetonka in Hennepin County is down to its lowest level since the 2012 drought.
For the full USDA report for Oct. 6, click here.