Split Upper Level Flow Keeping Us Away From Bitter Chill

The past couple of nights have been blow freezing, but tonight will break the streak. Additionally, in the near term, the hard cold will fade out and a gradual warm up gets underway. One of the largest contributors to the slight increase in temperatures comes from the wind flow in the upper levels of the atmosphere. What occurs in the upper levels translate down to the surface, where we live.

Approximately 35,000 feet above the ground, there are two jet streams that are crossing the United States at this time. The following image denotes where each jet stream is flowing:

Note in the image above the Sub-Tropical jet stream and the Polar jet stream. At the moment, the Sub-Tropical jet stream is moving above the Lone Star State. Furthermore, this stream is coming off of the Pacific Ocean. Due to this flow off the Pacific, the air is able to moderate and soak in additional moisture. Therefore, we are experiencing a "cool" flow. 

On the flip side, the Polar jet stream originates from northern Canada. As the word Polar denotes, much colder air can spill in from this upper level feature. Typically in the winter, the Polar jet stream delivers very dry air, with a bitter bite. Due to the location of this jet stream at the moment, the coldest air across North America will stay well north of Texas. In addition, latest computer guidance suggest that this feature will stay well north for the next couple of weeks. In other words, the frigid air will stay away from us for now.