Severe storms still questionable, but something different/troubling possibly ahead

Chances are looking good for thunder this coming weekend, possibly as early as Friday, but whether or not said thunder will be accompanied by severe weather hazards remains in question.  As of now, I'm leaning toward a less robust storm mode spread out over several days rather than one big whopper, which will likely mean lower chances of severe weather.

Looking ahead, I am noticing something a bit discouraging for the month of August, and it has nothing to do with thunderstorms.  The last few long term model runs are beginning to hint that the upper air pattern for August is going to change significantly from the one we were experiencing in July.  What's troubling to me is that it resembles less of what we tend to see in the summer, and more like what we've seen over the last couple of winters.

Hello, Old Man...

See that red circle?  Yep, that's a chunk of our old "friend", Mr. Polar Vortex.  If this forecast should verify, we can expect the "summer-like" temperatures we've been having for the past little while to disappear.  Night time lows could even sink as far as the 40s in some places.

Expect surface temperatures to plummet should this forecast verify.

What really gets me about this is that it's demonstrating that the pool of warm air in the Gulf of Alaska not only remains, but remains very strong.  It also seems to be having a greater impact on our weather patterns than even the moderately strong El Niño that has developed in the Pacific.  Normally, during a moderately strong El Niño, we can expect a mild winter in Michigan.  This could still be the case, however, should this pattern persist into the winter, what we may wind up with instead is the same pattern we saw the last couple years with brief warm-ups accompanied by potentially stronger-than-average clipper systems, which are able to take advantage of extra moisture provided by El Niño, and the occasional winter storm whopper from the south. 

Andrew, a blogger I've followed extensively over the past couple years, released his preliminary 2016 winter forecast the other day.  Sure enough, he mentions both of these phenomena, and suggests that winter could pretty much go either way in our neck of the woods.  This lowers my confidence in the previously widely-anticipated "mild winter" I was (and I'm sure many other Michiganders were) hoping for.

As far as the remainder of summer goes, I'd expect a pattern like this will also likely increase thunderstorm chances, but for now the GFS is suggesting that most of the stronger storms will be to our south in the Ohio valley, where warmer, more unstable air will be present.  This could be disrupted by the "heat dome" building to our south rather than surging northward into Montana as is currently predicted.  In that case, our chances for big thunder and severe weather will skyrocket.  Those hoping for super-hot 90°+ days will likely be out of luck.