Posted on 10/19/2017 8:50 AM

The National Weather Service's (NWS) forecast for November through January calls for above-normal temps across much of the contiguous U.S., including the Central and Southern Plains as well as the Corn Belt. The exception is a band from Washington to western Minnesota that calls for equal chances of normal, below- or above-normal temps. Additionally, the forecast calls for below-normal precip from Arizona into the Carolinas. This includes Oklahoma and Texas. However, given that the latest Drought Monitor indicates a limited presence of drought, the winter outlook for the HRW wheat crop is not overly concerning.

Above-normal precip is expected from Montana southward into Colorado, while the Dakotas, Central Plains and the Corn Belt have equal chances of normal, below- or above-normal precip for the winter months.

The NWS adds that oceanic conditions continue to move "quite close to the La Nina state." It says the outlook took into consideration the impacts "often observed during La Nina events."

“If La Nina conditions develop, we predict it will be weak and potentially short-lived, but it could still shape the character of the upcoming winter,” said Mike Halpert, deputy director of NOAA’s Climate Prediction Center. “Typical La Nina patterns during winter include above-average precipitation and colder-than-average temperatures along the Northern Tier of the U.S. and below-normal precipitation and drier conditions across the South.” 

Other factors that influence winter weather include the Arctic Oscillation, which influences the number of arctic air masses that penetrate into the South and is difficult to predict more than one to two weeks in advance, and the Madden-Julian Oscillation, which can affect the number of heavy rain events along the West Coast, notes the agency.

NWS outlooks for November through January:

90 temp

 

90- precip

 

In its outlook for November, the NWS calls for above-normal temps across much of the wesern states, including Nebraska southward through Texas. Across the Dakotas and Midwest chances are equal for normal, below- or above-normal temps. Below-normal precip is favored along the Gulf Coast, while above-normal precip is favored in Montana. Elsewhere, chances are equal for normal, below- or above-normal precip.

The NWS says the November outlook can be "challenging," which is amplified as the response to ENSO is "not yet fully mature" at this point. It adds, however, there is a La Nina footprint, as atmospheric conditions are moving closer to the La Nina state.

NWS outlooks for October:

30 temp

 

30 precip

 

Below, we compare the Seasonal Drought Outlook to the current Drought Monitor:

seaonal drought

 

drought

 

The seasonal drought outlook states 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," it states.

Additionally, small areas of moderate drought are expected to linger through the winter across portions of the Ozarks, middle Mississippi Valley and Corn Belt. "NDJ (November-January) 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," it adds.

However, persistence of drought across the Southeast, lower Mississippi Valley and east Texas is consistent with the seasonal precip outlook, states the NWS. "Due to heavy and excessive rainfall associated with Hurricanes Harvey, Irma and Nate, the coverage of development is limited for this outlook," it adds. "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. "


 

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