So this is what December feels like. The first half was nearly 14F warmer than average in the Twin Cities with 7 nighttime lows at or above 32F. Remarkable.
What's really going on? It's overly simplistic to point only to El Niño. Yes, that's a huge signal, but so is the additional warming of the atmosphere and oceans, which will make 2015 the warmest year on record, worldwide. But the Arctic Oscillation is another factor, a strong positive value reflecting unusually low pressure over the Arctic region. When this happens the dreaded polar vortex tends to stay over far northern latitudes, with fewer intrusions of Siberian air into the USA. We've seen no signs of an imminent shift that would divert polar air into Minnesota.
Until that happens we'll see more slop-storms with temperatures near freezing; more neutered cold fronts. Enjoy 20s today and Friday, but Pacific air blows more 30s into town next week; 40F possible by next Wednesday
Snow? Maybe a cosmetic coating Monday morning. Can I interest you in a beige Christmas?