Here is a look at the mid-level pattern this time next week, January 18, 2021, from the GEFS. The key features are seen around Greenland, Hudson Bay, and western Canada. Also, pay attention to areas east of Hawaii. If you notice the orange, red, and brown colors around Geeenland and western Canada, you should see the blue and purple colors along Hudson Bay. That is the "in"famous polar vortex that we track during most winters. When we have that scenario, look for cold weather in the central and eastern United States. So what about the connection east of Hawaii? If you see blue in that locale, there is good support for an active subtropical jet. This leads to frequent storm threats. When all these features are in place during this time of year, winter should be quite prevalent in the central and eastern United States.

Here is a look at the Canadian ensemble, which is quite similar in makeup to that of the GEFS. We notice ridging (red) along Greenland and western Canada, with troughing (blue) along Hudson Bay. To the south, cold air is spilling into the central and eastern USA.

This is the European Ensemble Mean. As its two predecessors have shown, this ensemble matches up well to our line of thinking. Ridging and troughing are in the right areas, and could lead to colder and stormier weather in the days to come. If more pronounced troughing can set up east of our 50th state(Hawaii), storm impacts will be even greater. Winter impacts will start to grow by the end of this week and continue through the rest of January.

Forecast Provided By: Meteorologist Joshua Ketchen