Latest Monthly Assessment -
Heavy to excessive rainfall resulted in a decrease in drought coverage across the central and southern Great Plains along with the Mississippi Valley during September. Drought coverage in Texas peaked at 64 percent on September 4 but decreased to 20 percent by the final week of September. Drought expanded and intensified slightly across much of the western U.S. and northern Great Plains during the past month. Much of the eastern U.S. remains drought-free except for small areas of the Southeast, Maine, New York, and Vermont.
The monthly drought outlook valid for October 2018 is based on 7-day precipitation forecasts, extended range (6-10/8-14 day) precipitation and temperature outlooks, the CPC updated October precipitation and temperature outlooks, and climatology. Recent rainfall and soil moisture forecasts from the GFS model were also considered.
Heavy rain, associated with the remnants of Hurricane Rosa, at the beginning of October along with a continued wet pattern through the second week of October favor drought improvement from the desert Southwest north into the Great Basin and central Rockies. Despite the expected improvement, long-term drought impacts may persist. Improvement and removal of drought are forecast from the Great Plains east to the Great Lakes and Northeast where above-normal precipitation is likely during early to mid-October. Drought development is expected to be limited to parts of Georgia and South Carolina due to 30-day precipitation deficits along with the likelihood of below normal precipitation and above normal temperatures through at least early October.
Although the monthly outlook calls for increased chances of above normal precipitation throughout much of the western U.S., amounts are not expected to be sufficient to result in broad scale improvement across California, New Mexico, and southeast Colorado. Enhanced odds for above normal precipitation during October are also forecast across the northern high Plains, but an increasingly dry climatology favors persistence across northeast Montana and northwest North Dakota.
Drought improvement or removal is expected along the Alaska Panhandle due to a wet climatology. Removal is also anticipated for any lingering drought across the Hawaiian Islands. Puerto Rico is forecast to remain drought-free through the end of October.
Forecaster: Brad Pugh
Next Monthly Outlook issued: October 31, 2018 at 3 PM EDT
Monthly Drought Outlook Discussion