Winter Outlook: Continued Drought in U.S. Southwest

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Photo By: NOAA

A resurgent La Niña will continue to starve the desert Southwest of moisture through the winter, according to the annual Winter Outlook produced by the National Oceanographic and Atmospheric Administration.

While the focus of the winter outlook is typically on temperature and snow expectations for the northern half of the country, the continuation of drought centered on Texas is the most alarming feature of the forecast. By some measures, the drought there is already worst than the Dust Bowl of the 1930s that inspired massive migrations and social change.

La Niña, defined by a colder-than-usual temperature pattern in the Southern Pacific Ocean, like its antecedent El Niño, produces predictable weather patterns across continents, including colder and wetter conditions in the Pacific Northwest. But NOAA warns that La Niña's influence could be masked or amplified by the so-called Arctic Oscillation, a variable and more difficult-to-predict pressure pattern over the Atlantic with strong influence on weather patterns.

When the Arctic Oscillation is in a negative phase, as it has for extended period the past two winters, cold and often stormy Canadian air floods the U.S. The results included the so-called "Snowmaggedon" storm of 2009.

But on the whole, the drought is expected to remain the biggest U.S. weather story.

The animation below, also from the U.S. Drought Monitor, shows how the drought has spread over the past 12 weeks.