November to January 2019 Temperature Outlook: Mild in the North, Chilly in the South

While many residents in the central and eastern United States are expected to endure a cold latter half of October, a pattern flip is in the forecast for November, which could bring milder temperatures back to those who are shivering now.

Warmer-than-average temperatures are forecast in November from the West Coast to the northern Plains and much of the Midwest, with below-average temperatures likely in the southern Plains, according to the latest outlook from The Weather Company, an IBM Business. The warmest temperatures relative to average should be found in the northern Rockies, northern Plains and upper Midwest.

(MORE: Pattern Change to Finally Usher in Fall-Like Conditions in East, Midwest)

A swath from the Southwest to the central Plains, mid-Mississippi Valley, Ohio Valley and Northeast is expected to see near- or slightly above-average temperatures during November. Meanwhile, near- or slightly below-average temperatures are forecast from the southern Plains to the Appalachians, Southeast and mid-Atlantic region.

"We’ve reduced forecast temperatures a bit in the eastern U.S. for November and have increased them across the northern Rockies and Plains, given the expected Arctic Oscillation trends later in the month and the contrarian ECMWF (European model) guidance," said Dr. Todd Crawford, chief meteorologist with The Weather Company.

Crawford said the positive phase of the North Atlantic Oscillation (NAO) – and positive phase of the Arctic Oscillation – which has prevailed through most of 2018, may finally be fading away. One consequence of this could be an increased chance of colder air reaching parts of the eastern states.

A positive NAO means an upper-level trough of low pressure is in place near Greenland and typically correlates with warmer temperatures in the eastern United States. When the NAO trends negative, high pressure builds near Greenland, and cold air can be drawn southward into the eastern U.S.

"Given the evidence discussed, along with the cooler (and historically more reliable) ECMWF ideas for November, we have reduced forecast temperatures across the eastern U.S. and increased them across the northern Plains," Crawford said.

(MAPS: Average High and Low Temperatures)

This overall weather pattern of milder temperatures toward the north and colder temperatures toward the south is currently expected to continue into the start of winter.

December

Far above-average temperatures are expected in the Northwest, with warmer-than-average temperatures also anticipated from northern California to the northern Plains, upper Midwest and northern Great Lakes.

Near- or slightly above-average temperatures are forecast from Southern California and the Southwest to the central Plains, Midwest and Northeast.

Areas along the Gulf Coast, from Texas to the Florida Panhandle, are expected to endure colder-than-average temperatures during winter's first month.

A broad swath from southeastern New Mexico to the southern Plains, mid-Mississippi Valley, lower Ohio Valley, Appalachians and Southeast should see temperatures near or slightly above average in December.

January

Temperatures in January are expected to be similar to those in December.

The warmest temperatures relative to average are forecast across the far northern tier from Washington to North Dakota, with above-average temperatures also expected from northern and central California to the northern Rockies and northern Plains.

Near- or slightly above-average temperatures are forecast in a broad swath from the Southwest to the central Rockies, central Plains, upper Midwest and interior Northeast.

Areas along the immediate Gulf Coast and in the Southeast can expect a colder-than-average start to 2019.

Temperatures are forecast to be near or slightly below average along the Northeast coast and southwestward into the mid-Atlantic states, Appalachians, Ohio Valley, lower and mid-Mississippi Valley and southern Plains.

This predicted early-winter pattern of relative mildness in the northern states and relative coolness in the southern states is a common trait of El Niño winters. NOAA has issued an El Niño watch and projects a 65 to 70 percent chance of El Niño conditions by winter.