Wednesday, October 3, 2012

Long Range Lookout: Cold and Snowy Pattern Settling In

This is the October 3, 2012 issue of Long Range Lookout. Further Long Range Lookout posts will now be issued on Wednesday afternoons.

This is an analysis image of what was observed on September 22, 2012. This chart shows 500mb height anomalies across North America and the East Pacific. As you can see, a deep disturbance was present in the Great Lakes region, with a strong ridge in northwestern North America. Look familiar? It should feel familiar, as this disturbance brought many North US folks the first good cold shot as a result of this synoptic-scale pattern. It even brought some snow to the Upper Midwest. It was a total shock to many folks, who usually see their first freeze well into October. Snow fell several weeks before it should.

What we have been seeing no longer appears to be an anomaly. Cold across the board and snow in the Upper Midwest may actually be the norm if what I'm about to show you verifies.

This is the 240 hour forecast for the latest GFS model. I have outlined two areas of interest- the first is an arrow pointing east, denoting an active storm track. This is not something new- we have been seeing this active North Pacific storm track for quite a while now, and it is these systems that have produced the cold in the North.

Also, take note of the circled area of blues out ahead of the storm systems. It is known that before a storm system moves east into the West Coast of North America, a ridge can form out ahead and force the storm to change its path. Again, this has happened several times in the past few weeks. If this ridge holds, the storms will shoot north and dive south into the Great Lakes, sending cold and snow into the region, like we have seen earlier.

My point is, the cold is going to stick around in the next several days before a possible steady warm up occurs through much of the nation. However, this has yet to be examined and must be analyzed further to confirm this suspicion.


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