The heat wave affecting nearly 115 million people in more than 15 states is going to intensify significantly before conditions improve.

Why it matters: The heat is so severe and long-lasting that it constitutes a deadly threat in many areas, particularly across the Southwest and portions of the West. Extreme heat is the top annual weather-related killer in the U.S. and can cause harm indiscriminately and quickly.

• Human-caused climate change is worsening this heat wave by making it more intense, longer-lasting and more likely to occur.
• An initial analysis from research and communications nonprofit Climate Central shows that in some areas affected by this heat wave, climate change has made record-breaking temperatures at least 5 times more likely than in a world without the added amounts of heat-trapping greenhouse gases.

By the numbers: One remarkable aspect of this extreme heat event is how high temperatures are likely to get in cities that are typically thought of as very hot in the summer.

• In Phoenix, each day for the past two weeks has reached or exceeded a high temperature of 110F. The all-time record stands at 18 days, and high temperatures for the next five days or more are forecast to hit or exceed the 110-degree mark, virtually assuring the record will be tied or broken.
• Also in jeopardy is the record for the hottest seven days, to be set from Thursday through July 19. This is partly a result of extremely warm nighttime lows.
• The city may break its record...

Read Full Story: https://news.google.com/rss/articles/CBMiRWh0dHBzOi8vd3d3LmF4aW9zLmNvbS8yMDIz...