(CNN) -- The record combined land and ocean temperatures for the first six months of the year might have one thinking 2010 is on track to eclipse 2005 as the world's warmest year.
Not so fast, climatologists and weather watchers say.
Now that the approaching La Nina ocean current is on track to replace El Nino, Pacific waters will be colder than normal. Because of this, 2010 may not shatter the record, said CNN meteorologist Sean Morris.
The National Climatic Data Center reported Thursday that the global combined temperature of 57.5 degrees Fahrenheit was the warmest on record for January-June. That figure is 1.22 degrees above the 20th century average and breaks the 1998 mark.
Also, the combined land and sea temperature in June was the warmest on record at 61.1 degrees Fahrenheit, according to the report, or 1.22 degrees above the 20th century average.
The center reported that 2010 surpassed 1998 for the most warmest months in any single year.
Sea ice from the Arctic had its lowest June extent since records began in 1979. It covered 4.2 million square miles, 10.6 percent below the 1979-2000 average extent.
Not every place felt warmer. Spain experienced its coolest June "temperature anomaly" since 1997, according to the country's meteorological service.
The climate center has kept records since 1880.