Drought persistence across the Plains, Midwest & Southeast

(Brownfield) – The drought outlook for September 15, 2011 – December 2011 was based primarily upon climate anomalies associated with La Niña as it is expected to strengthen and continue throughout this period.

Persistence or development can be expected across much of the Southeast excluding North Carolina and areas soaked by Tropical Storm Lee. The return of La Niña also elevates the chances for persistence across the exceptional drought areas of the southern Plains. It should be noted that forecast confidence across the western Gulf region and Southeast is tempered due to the potential for heavy rainfall associated with tropical cyclone activity during the fall.

The waning of the summer monsoon and enhanced odds for below median precipitation during October – December favor persistence or development across most of the Southwest.

Based on consecutive La Niña composites, persistence or development is favored across the middle Mississippi Valley and lower Ohio Valley. A slightly drier climatology from October through December tilts the odds towards persistence for the small drought areas in the northwest Corn Belt and upper Mississippi Valley.