Every month University of Alabama in Huntsville climatologists John Christy and Roy Spencer publish the latest global temperature trend data obtained from NOAA satellites. For the month of October 2015 they report:
In the Northern Hemisphere, October 2015 registered the third largest deviation from seasonal norms in the 443 month satellite temperature record, making it the third "warmest" month in the Northern Hemisphere since December 1978. October 2015 trailed only April 1998 (+0.85 C) and February 1998 (0.69 C) as the "warmest" month in the Northern Hemisphere.
"We thought this El Niño had the potential to be a record setter for some of the quantities we track, and it isn't disappointing," Christy said. "Not only is this a strong El Niño, but the transient warming we see from it is superimposed on top of the slowly rising global base temperature. The satellite temperature dataset shows an overall warming of about 0.39 C during the past 36 years. Put a strong El Niño on top of that and we shouldn't be surprised at what we saw in October."
Global Temperature Report: October 2015
Warmest October in the satellite temperature record
Global climate trend since Nov. 16, 1978: +0.11 C per decade
October temperatures (preliminary)
Global composite temp.: +0.43 C (about 0.77 degrees Fahrenheit) above 30-year average for October.
Northern Hemisphere: +0.64 C (about 1.15 degrees Fahrenheit) above 30-year average for October.
Southern Hemisphere: +0.21 C (about 0.38 degrees Fahrenheit) above 30-year average for October.
Tropics: +0.53 C (about 0.95 degrees Fahrenheit) above 30-year average for October.
(All temperature anomalies are based on a 30-year average (1981-2010) for the month reported.)
Warmest Octobers, Global
Date Warmer than seasonal norms
2015 +0.43 C
1998 +0.40 C
2003 +0.29 C
2005 +0.28 C
2014 +0.26 C
Go here to see their complete set of monthly data since 1978.