On May 9, the daily mean concentration of carbon dioxide in the atmosphere of Mauna Loa, Hawaii, surpassed 400 parts per million for the first time since measurements began in 1958. It marks an important milestone because Mauna Loa, as the oldest continuous carbon dioxide (CO2) measurement station in the world, is the primary global benchmark site for monitoring the increase of this potent heat-trapping gas.

In its 2013 Atlantic hurricane season outlook issued today, NOAA’s Climate Prediction Center is forecasting an active or extremely active season this year.

NOAA’s Climate Prediction Center announced today that a below-normal hurricane season is most likely for the Eastern Pacific this year. The outlook calls for a 55 percent probability of a below-normal season, a 35 percent probability of a near-normal season and a 10 percent probability of an above-normal season.

Get the latest forecast, watches and warnings from NOAA's National Weather Service Storm Prediction Center, http://www.spc.noaa.gov.

NOAA’s Central Pacific Hurricane Center today announced that climate conditions point to a below-normal season in the Central Pacific Basin this year.

Get late-breaking weather information, and your local forecast, at http://www.weather.gov.

Get late-breaking information from the NOAA National Weather Service Storm Prediction Center (http://www.spc.noaa.gov/).

This year, more than 80 million Americans will enjoy boating with friends and family. The National Safe Boating Council and the NOAA's National Weather Service have partnered to support boating safety by creating relevant, weather and safety-specific public service announcements for National Safe Boating Week, which runs from May 18 to 24..

According to NOAA scientists, April 2013 was also the 37th consecutive April and 338th consecutive month (more than 28 years) with a global temperature above the 20th-century average.

NOAA presented to the U.S. Coast Guard today a new report that finds that 36 sunken vessels scattered across the U.S. seafloor could pose an oil pollution threat to the nation’s coastal marine resources.

As recreational boaters gear up for a summer of fun on coastal waters and the Great Lakes, NOAA is testing MyNOAACharts, a new mobile application that allows users to download NOAA nautical charts and editions of the U.S. Coast Pilot.