Below average temperatures to end October for much of the country
October is forecast to end on a cold note across a large part of the country as a large pattern change takes shape. This pattern change will take shape by the end of the week, forcing cold air out of Canada into United States.
Watch the explanation on why cold air will slip south into the United Sates here: http://bit.ly/2NhoS5d.
Numerical guidance, which is referred to as “computer models” by meteorologists, is a tool meteorologists use to help determine the future state of the atmosphere (i.e. what will happen in your area tomorrow or in 5 days). This guidance is indicating a equatorial dip in the jet stream across the central United States as the Eastern Pacific Ridge and Greenland Block establish, creating a “buckle” of the jet stream. This will force the jet stream south, allowing cold air to readily flow into central parts of the country.
Figure 1: Late October upper-level pattern
Figure 2: Late October frequent cold fronts
The Climate Prediction Center (CPC) has highlighted the majority of central & western parts of the country for moderate to high probabilities of below average temperatures for days 6 through 10.
Figure 3: 6 to 10 day temperature outlook (CPC)
The CPC also has the same areas with moderate to high probabilities of below average temperatures for days 8 through 14, which will cross over from the end of October into the beginning of November.
Figure 4: 8 to 14 day temperature outlook (CPC)