ACCORDING to the NOAA's (National Oceanic and Atmospheric Administration) data center, in September 2013 the globally-averaged temperature across land and ocean surfaces combined was 0.64°C (1.15°F) higher than the 20th century average, tying with 2003 as the fourth warmest September since records began in 1880. September 2013 also marks the fifth consecutive month (since May 2013) with monthly-average global temperatures ranking among the six highest for their respective months.
Considering land surfaces only, the globally-averaged temperature was the sixth highest on record for September, at 0.89°C (1.60°F) above average. The Southern Hemisphere was record warm for the month, with an average land temperature that was 1.20°C (2.16°F) higher than average, the third highest monthly anomaly for any month (behind August 2008 and November 2009) in this hemisphere in the 134-year period of record. This warmth was due largely to record-high temperatures observed across most of the Australian continent. The average Northern Hemisphere temperature was also well above the 20th century average, at 0.77°C (1.39°F) above average and ranking as the 10th highest for September on record. Record warmth was observed across part of central Asia, stretching into southern Asia and the Middle East, as well as part of southwestern Canada. Most of central and northern North America, northern Europe, and much of central and southern Asia were much warmer than average. Cooler and much-cooler-than-average temperatures occurred across much of central and eastern Russia, along with most of eastern Europe and western Greenland.
Averaged across the world's oceans, September 2013 tied with 2006 as the fourth highest September temperature, at 0.54°C (0.97°F) above the 20th century average of 16.2°C (61.1°F).
The globally-averaged temperature for the first nine months of 2013 (January–September) was 0.60°C (1.08°F) above the 20th century average of 14.1°C (57.5°F), tying with 2003 as the sixth warmest such period since records began in 1880. The average global land temperature for this period was the seventh warmest on record, at 0.93°C (1.67°F) above the long-term average. Notably, Australia, the southern Philippines, and part of central Asia were record warm for January–September. The average global ocean temperature for the first nine months of 2013 was also the seventh warmest in the 134-year period of record, at 0.48°C (0.86°F) above average.
From NOAA's National Climatic Data Center