Bimonthly daily extremes in excess of the lower estimate for 20-yr events for November-December 2017
November-December 2017 recorded a national tally of “only” 7.5% of all 866 available stations with 20-yr daily extremes (for the first time dropping below 90% of the original set of 987), not nearly as high as during years during the last decade (only 2012 was lower since 2003). The national trend is still upward (+2.8%/century) through 2017 (p=97%). Only the Ohio Valley exceeded 10%, actually by quite a bit with 24.8%, ranked 11th highest since 1901. This confirms a highly significant regional upward trend (3.2% per century; p=99.8%). On the other hand, the neighboring Midwest had one the lowest counts on record with 0.9% (tied for 14th lowest), during a season with no significant trend.
There was one Billion-Dollar Disaster ( https://www.ncdc.noaa.gov/billions/events) that picked up where October had left off: Southern California experienced extreme wildfire conditions in early December that culminated in the Thomas Fire complex ( https://en.wikipedia.org/wiki/Thomas_Fire). It burned 440 square miles to make it the largest wildfire in California’s recorded history, and killed two people while causing damages in excess of $2B.