Charts: 1938 - 1941 Global Average Temperatures
by Climate at a Glance | National Centers for Environmental Information (NCEI)
"2016 will make a hat trick for 2014-16: three years in a row setting a new record. That’s rare. With the exception of 1939-41, when the NOAA time series was barely in statistical adulthood, this is only time the modern record yields three straight 'warmest years on record.'"[1]
Please note, Global and hemispheric anomalies are with respect to the 20th century average.