The heat wave baking the U.S. Pacific Northwest and British Columbia, Canada, is of an intensity never recorded by modern humans. By one measure it is more rare than a once in a 1,000 year event — which means that if you could live in this particular spot for 1,000 years, you’d likely only experience a heat dome like this once, if ever. CBS meteorologist and climate specialist Jeff Berardelli joins CBSN’s Lana Zak with more. Source