Mid-Summer Update - Boosting Temperatures but Precipitation Variability Remains Intact

On my original Outlook, I was looking for temperatures to average up to 1.0 degree above normal for the summer as a strong ridge over the south-central US routinely battled for dominance the upper cool Canadian Low over eastern Canada. This pattern was the one mentioned and preferred in the Outlook. The Canadian upper air cool downs have become less frequent and notable with time as the upper ridge strength continues to  be impressive as we enter the hottest part of the climatological summer.

From the original Outlook:

Overall, I look for summer temperatures to average around normal (-.5 to +1.0). Local analogue data for this summer generally shows normal to below normal averages. At the same time, projections for the upper wind pattern suggest ridging over the south-central part of the country will periodically expand into the Great Lakes bringing more heat into the region. The temperature outlook is a tough call and will mainly depend on the how strong the ridge becomes and its placement. At this time, it looks like the ridge will oscillate from just to our west (Midwest) to the eastern third of the country. This will bring periods of heat and cool downs (while working in conjunction with the upper low in Eastern Canada). Number of 90 degree days should be about average for the summer, 8-12.

The preferred pattern has indeed evolved (and then some) and is why I leaned toward an above normal departure (which was against the dominant analogues). The upper air pattern projections continue to show signs of the hot ridge nosing (as of 7/15/11) routinely into the Great Lakes with heat and subsequent humidity much of remainder of July and this looks good. 

I have decided to up my temperature departure for the summer to 1 1/2 to  3 degrees above normal. As far as 90 degree days, I originally went 8-12 days for the entire region. I will also boost that to 11-15 for the Detroit and Flint areas but remain with the original projection for the Saginaw Valley region

Further Out>>>
It will be interesting to see if the pattern of the analogues which showed the cooler (relative to normal) part of the summer coming in the second half. If that does occur, and usually the analogue projections are better at the overall pattern than their numerical departures, then August should contain closer to normal or possibly below temperatures. We shall see. 

I see no need for precipitation changes as strong variability remains dominant. Some areas have had more than enough rain while others are dry and this is very similar to 2008.

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