Since 1990, there have only been 7 Dec-Mar winters in which the AO/NAO combo was negative [I used (AO+NAO)/2 = -0.40 or lower]. Maybe surprisingly, 5 of the 7 occurred during La Nina/Cool ENSO, with 2 during El Nino/Warm ENSO pic.twitter.com/A2dm5MtlrM

— griteater (@griteater) September 25, 2020