Coldest Air of the Season On the Horizon

UPDATE 09/06/14
Updated dates below to reflect model runs of the Euro Model. 7-10 days out does not go beyond the 16th. I had posted dates beyond that for some reason.
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Here we go again...talk of another Polar Vortex coming soon to the United States? I hope the media and some meteorological sources do not hype this thing up again like previous instances.

However, admittedly, when I looked at a recent run of the ECMWF, which is the model of choice for me at 7-10 days out, the depiction of a deep trough spinning above the Hudson Bay with spokes of cold air funneling toward the U.S. border tells me that the growing season may be coming to an end soon for some residents of Minnesota and the U.P. of Michigan.

Now, I am not talking this weekend but maybe next weekend. But, a consistent signal is showing up that by the September 13-15 time frame, a nice blast of very cool air may be invading initially the northern portions of the upper Midwest then surging southward toward our region of Kentucky.

The 00z run for Sunday evening of September 14 shows some serious cold near the Hudson Bay. The question is how much modification of that cold air will take place as it surges southward toward the northern U.S.?

Looking down the road, I would not be surprised to see overnight low readings here in Louisville drop to the mid 40's with upper 30's to low 40's in the outlying areas by the 14th. And that may be conservative. Depending on cloud cover, some areas may struggle with getting out of the 50's for highs!

This is just a preliminary look at what could happen. There's a lot of uncertainty concerning the details but does show our first blast of autumn air poised to infiltrate the region within the next two weeks.

Stay tuned...

MS