11:45 AM | *A split nation next 6-10 days…colder than normal western half…warmer than normal eastern half*

Colder-than-normal weather is in store for the western US in coming days and warmer-than-normal in the eastern half of the nation. Map courtesy NOAA, tropicaltidbits.com

Overview

The next week to ten days or so will feature quite differing weather conditions across the nation with colder-than-normal temperatures across the western half and warmer-than-normal in the eastern half.  An upper-level trough of low pressure will park itself over the western US in coming days and a strong ridge of high pressure will center itself over eastern Canada and the eastern US.  By the third week of October, this upper-level ridge of high pressure may “retrograde” back into central Canada and this shift could allow for a big cool down in the Mid-Atlantic/Northeast US by the 18th or 19th of October. 

The upper-levels will be dominated by a trough of low pressure out in the western US and a strong ridge of high pressure over eastern Canada/Great Lakes and the eastern US. Map courtesy NOAA, tropicaltidbits.com

Discussion
Much different weather conditions will take place across the nation in coming days with colder-than-normal weather out west and warmer-than-normal across much of the eastern half of the country.  The cold out west will accompanied by some accumulating snow as well with several inches possible during the next ten days in the Rocky Mountain States of Wyoming and Colorado and perhaps in the Sierra Nevada Mountains of eastern California as well.

NOAA’s 6-10 day temperature outlook features a divided nation with cold out west and warmth in the east. Map courtesy NOAA

Meanwhile, the eastern half of the nation will feature well above normal temperatures for the short and medium term with the 70’s for highs a certainty in the Mid-Atlantic and even the 80’s may be reached in some spots of the I-95 corridor. Strong upper-level ridging will first concentrate itself over the eastern part of Canada and the Great Lakes – with an extension coming down through the eastern US – and then it may begin to shift westward at mid-month (i.e., retrograde). This shift to the west in the upper-level ridge could very well “open the door” for a cool down in the Mid-Atlantic/Northeast US by the third week of the month – and after this balmy stretch of weather that is on the way for the next 6-10 days.

Snow could pile up over the next 10 days or so in some of the higher elevation locations of the Rocky Mountain States. Map courtesy NOAA, tropicaltidbits.com

Meteorologist Paul Dorian

Video discussion: