About 90% of the contiguous United States is sweltering with the summer sun, while the Pacific northwest is fairly pleasant. Why is this such a wacky summer? Mark Thibodeau with the Weather Channel says it's just an unusual pattern: “We really do have a classic heat wave building across much of the United States. Central and Eastern U.S. in particular. We are still north of the jet stream, where it lies. And usually in that happens, you tend to be in the cooler air. And what's happen is the rest of the country, the central plains, northern plains, eastern United States, the jet stream has retreated into southern Canada. That’s allowed all this hot air to build up underneath a strengthening July sun angle to move northbound, strengthening underneath this high pressure and it's just really gotten a grip." Thibodeau says while we could get a possible thunderstorm today, later this week things will dry out and heat up into the mid 80's by Sunday.