Relentless November Arctic Cold In Plains, Midwest, Rockies to Last Into Next Week

By Jon Erdman 
Published: November 10, 2014

  http://www.wunderground.com/news/arctic-cold-outbreak-november-locked-20141110

A potent blast of arctic air is plunging into the nation's mid-section and south this week, sending temperatures crashing to values you might expect in mid-winter. And it may last a while!

The leading edge of the cold blast plunged through the Plains on Monday. In many places, temperatures fell 20 to 30 degrees in less than one hour, and strong winds kicked up a dust storm across the southeast quarter of Colorado.

First, we'll hit some cold highlights in both forecast highs and lows, then ask how long this will last.

Forecast High-lights:

Highs much of this week should hold in the teens or 20s in the northern Rockies, northern Plains and Upper Midwest. Some snow-covered areas of the northern Rockies and northern High Plains may struggle to rise out of the single digits. 

Casper, Wyoming, is one of those cities that may have a day in which the high fails to rise out of the single digits. The earliest-in-season date on record with a single-digit high or colder was Nov. 15, 1955. 

Daytime highs in the 30s and 40s will become widespread by mid-week from parts of the southern Plains to the Ohio Valley, northern Tennessee Valley and southern Appalachians. 

Some of these daily high temperatures will be more on par with average January highs, rather than November.

Forecast Low-lights

Subzero cold is expected to be most widespread in the fresh, snow-covered areas of the northern Rockies and High Plains. Later in the week, some of the areas that received heavy snow from Winter Storm Astro in the northern Plains and Upper Midwest may also dip below zero, as well.

Single-digits and teens are possible into the central High Plains of eastern Colorado and western Kansas, as well as other parts of the northern Plains and Upper Midwest.

Lows in the 20s will plunge deep into the southern Plains and Deep South and spread into the Ohio Valley, Tennessee Valley and Southeast by later in the week.

How Long Will This Last?

While there will be some daily record lows threatened over the next several days, what will stand out about this cold snap is its longevity.

Above is a European model forecast loop through early next week depicting where the coldest air will be.

With blocking high pressure aloft over eastern Alaska and northwest Canada, a direct pipeline of cold air will come from Siberia to near the North Pole, then southward into Canada and the U.S., particularly the Plains and Midwest.

This is a classic Arctic outbreak pattern that will remain largely locked in over these areas through at least early next week, before potentially easing a bit along its southern edge later next week.

For example, forecast highs in the Twin Cities may actually be a bit colder next week, and will be below freezing. This will rival the longest November subfreezing streaks on record there (see graphic at right). Many of those days will see daytime highs colder than their climatologically coldest average highs in January (23 degrees).

After highs topped out near 80 degrees in Dallas Monday, highs into early next week will do no better than the 50s. In fact, several days may not see highs get out of the 40s, there. For reference, average highs in Dallas during the coldest time of year (late Dec. into early Jan.) are in the mid-50s.

Oklahoma City may not see the 50-degree mark until early next week, after soaring to 80 degrees Monday. Their average high in early January is 49 degrees.

There are also indications in our medium-range guidance that the heart of the cold, relative to mid-November averages, may shift toward the Great Lakes, Ohio Valley and East later next week. For instance, highs in Washington, D.C. may hold in the 40s much of next week.

Given this cold air in place, we will keep a close eye on any jet stream disturbance rippling through. Each has the potential to produce snow, sleet or freezing rain.