Pennsylvania: Cool summer

It was 1985 when temperatures in the region last failed to crack 90 in June and July, at least according to official temperatures logged at Lehigh Valley International Airport, said Kristin Kline, a National Weather Service meteorologist.

This month's average daily temperature was 68.6 as of Friday, about 5 degrees cooler than normal, a blessing in many ways but a downer in others.
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Bob Leiby, director of the Penn State Extension in Lehigh County, said the cooler, wet weather has meant troublesome fungal diseases, particularly for wheat crops, which have been been hit with fusarium, also known as ''scab.'' ''It has caused some problems for marketing the wheat,'' Leiby said.

Clouds Appear to Be Big, Bad Player in Global Warming -- Kerr 325 (5939): 376 -- Science

The first reliable analysis of cloud behavior over past decades suggests—but falls short of proving—that clouds are strongly amplifying global warming. If that's true, then almost all climate models have got it wrong...One interpretation, the researchers say, is that the warming ocean was transferring heat to the overlying atmosphere, thinning out the low-lying clouds to let in more sunlight that further warmed the ocean. That's a positive or amplifying feedback.

Again, this explains why in the past, every slight warming has been amplified by runaway positive feedback until all life on Earth was snuffed out.