We just had the 2nd highest global 3 month temperature anomaly ever - and not in an El Nino
NASA's figures for February are out: https://data.giss.nasa.gov/gistemp/tabledata_v4/GLB.Ts+dSST.txt
Dec 2015-Feb 2016 was an anomaly of 1.23C; Dec 2019-Feb 2020 was 1.18C, and all others (lower. The monthly Feb 2020 anomaly was 1.26C; only Feb and March 2016 (after the largest El Nino for years) were higher.
Same goes with the NOAA dataset:
What winter? Earth just had its second-warmest December-February on record
The months of December, January and February which meteorologists define as winter here in the Northern Hemisphere were the second-warmest on record, federal scientists announced Friday.
Only the El Niño-fueled winter of 2015-16 was warmer, the National Oceanic and Atmospheric Administration said. El Niño, a natural warming of sea water in the tropical Pacific Ocean, acts to boost global temperatures.
...
"Record-warm December to February temperatures were observed across much of the western half of Russia and parts of Europe, eastern Asia, northern Australia and across the Atlantic, Indian and western Pacific oceans," NOAA said. "However, no land or ocean areas had record-cold December to February temperatures."
https://eu.usatoday.com/story/news/world/2020/03/13/climate-change-earth-had-second-warmest-winter-record/5043841002/