Latest Seasonal Assessment -
Long-term drought over the northern Great Plains is expected to continue during the Oct-Nov-Dec (OND) 2017 season, with the region now in its climatological dry season. Other areas where drought is forecast to persist and/or intensify include eastern portions of the Middle Mississippi Valley, Lower Michigan, far southern Texas, western Nebraska, parts of Utah and Colorado, southern California and southern Arizona. This is due to a combination of factors, a few of which include sufficient distance from anticipated storm tracks, various dynamical and statistical model output, official precipitation forecasts at all timescales out to 90-days in the future, and the winding down of the summer Monsoon season in the Southwest. Two areas of potential drought development are indicated over the Middle and Lower Mississippi Valley and nearby areas, in regions where 30-day precipitation deficits are already substantial, and where most of the precipitation is expected to miss.
Drought improvement and/or removal is predicted from the Pacific Northwest to the northern Rockies based on good overall model agreement, and is consistent with what would be expected given the increasing odds of a upcoming cold season La Niña. Drought improvement and/or removal is also indicated across scattered parts of the Central contiguous U.S., generally from the Middle Rio Grande Valley through Kansas to the Upper Great Lakes region, based in part on the expectation of heavy precipitation in the shorter-term (next two weeks). With the approach of the cold season, and a climatological increase in widespread storm activity, the residual drought in eastern Maine is forecast to be removed.
The OND 2017 season is still a bit before the traditional rainy season for the Hawaiian Islands. Therefore, drought is predicted to either persist and/or intensify across the Hawaiian archipelago during the autumn. There is currently no drought in Alaska or Puerto Rico.
Forecaster: Anthony Artusa
Next Seasonal Outlook issued: October 19, 2017 at 8:30 AM EDT
Seasonal Drought Outlook Discussion