Monster Eastern US Trough To End October?

Written by Mark Vogan on October 20, 2015 in Autumn 2015, United States of America with 0 Comments

While a major Texas/Southern Plains flood event is ready to unfold with rich tropical moisture lifting north and merging with a strong cut off low sliding east out of the Four Corners, it’s the West Pacific that’s catching my eye.

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TWO typhoons look destined recurve. The ECMWF already has the monster trough diving into the East between day 7-10 as a consequence which could conceivably bring a record cold end to October. Last year, the recurve of Nuri set the playing for a very cold open to November for the US.

Credit: Tropical Tidbits

As these twin typhoons heat pump tropical heat energy into the mid and high latitudes, this causes amplification and deepening of the ridges and troughs forcing heat into the Alaska and the Arctic in the form of ridging which in turn drives early season arctic/Siberian air south.

Recurving west Pacific typhoons of course always catches the attention of American meteorologist as this can suggest an eastern trough while due west tracking typhoons which plough into Taiwan and China, often signal eastern ridging.

Note the increase in amplification in the below GFS 500mb height charts as we progress through this week into next with deepening troughs and ridging which pushes into the arctic, ultimately driving south the cold.