Latest Seasonal Assessment -
During the past month, drought improvement or removal occurred across the Pacific Northwest, northern Rockies, northern and central Great Plains, and the western Corn Belt. According to the U.S. Drought Monitor, valid on October 17, abnormal dryness (D0) and moderate drought (D1) expanded across parts of the eastern U.S. and lower Mississippi Valley.
The drought outlook from October 19, 2017 through January 31, 2018 is based primarily on initial conditions, 7-day precipitation forecasts, extended range (6-10/8-14 day) precipitation and temperature outlooks, the CPC November and November through January (NDJ) precipitation and temperature outlooks, and climatology.
The highest confidence for drought removal is across Washington and northern Idaho due to heavy precipitation forecast in the short-term and a wet time of year during the outlook period. Removal and improvement is also forecast for the northern Rockies. Although the seasonal outlook calls for increased chances of above normal precipitation across eastern Montana, a relatively dry time of year favors persistence on a broad scale. This persistence extends east to include the ongoing drought areas of the Dakotas.
Small areas of moderate drought exist across parts of the Ozarks, middle Mississippi Valley, Corn Belt, and New England. NDJ is a favorable time of year for soil moisture recharge and without a dry signal on the seasonal time scale, removal of these drought areas are anticipated by the end of January 2018.
Persistence is most likely for the ongoing drought areas across the Southeast, lower Mississippi Valley, and east Texas, consistent with the seasonal precipitation outlook. Due to heavy and excessive rainfall associated with Hurricanes Harvey, Irma, and Nate, the coverage of development is limited for this outlook. The potential for moderate to heavy rainfall during late October tempers the forecast confidence for development across the lower Mississippi Valley and Southeast. Confidence is higher for development for parts of south Texas, the Big Bend region of Texas, and the southwestern U.S., while long-term drought is likely to persist across southern areas of Arizona and California.
An increasingly wet climatology during December and January favors improvement and removal of drought across the Hawaiian Islands by the end of January 2018. Alaska and Puerto Rico are expected to remain drought-free .
Forecaster: Brad Pugh
Next Seasonal Outlook issued: November 16, 2017 at 8:30 AM EST
Seasonal Drought Outlook Discussion