If you want a glimpse of some of the worst of global warming, scientists suggest taking a look at U.S. weather in recent weeks. Horrendous wildfires. Oppressive heat waves. Devastating droughts. Flooding from giant deluges. And a powerful freak wind storm called a derecho. These are the kinds of extremes climate scientists have predicted will come with climate change, although it's far too early to say that is the cause. Nor will they say global warming is the reason 3,215 daily high temperature records were set in the month of June.