An Active Atlantic Hurricane Season Ahead?

  • Hurricane Sandy, 28 October 2012 (Credit: NOAA/NASA).

    The eye of Hurricane Gordon, as seen from the space shuttle on 18 September 2006. (Credit: NASA).

  • An Active Atlantic Hurricane Season Ahead?
    30.05.2013 14:06


    This Saturday (1st June) marks the start of the North Atlantic hurricane season, which runs for 6 months, through to the end of November. Complex climate and forecast models have been run, based on current ocean and atmospheric conditions, to predict how the season will play out. Evidence suggests that the 2013 season could well be “active” or “extremely active”, according to the National Oceanic and Atmospheric Administration (NOAA).

    NOAA’s Climate Prediction Center says there is a 70% chance of thirteen to twenty named storms this season. A storm is named when a sustained wind speed of 39mph is reached. Should the storm strengthen further and sustained wind speeds of 74mph are recorded, so the storm is classified as a hurricane. NOAA is expecting 7 to eleven such storms during 2013. Furthermore, NOAA has released details on how powerful these hurricanes could be. The Saffir-Simpson hurricane scale is often used to categorize the strength of hurricanes, based on a scale of 1 to 5, where a category 5 hurricane is the most powerful, having a sustained wind speed of over 156mph. Of those 7 to eleven predicted hurricanes, 3 to 6 of those storms are likely to reach category 3, 4 or 5 on the Saffir-Simpson hurricane scale (also known as major hurricanes). The one thing NOAA can not predict so far ahead is if, where and when hurricanes will make landfall.

    The predictions come based on three main factors. A strong west African monsoon, currently in place, which can help initiate tropical disturbances across the east Atlantic, where most hurricanes begin their life. Sea surface temperatures in the tropical Atlantic Ocean and Caribbean Sea are currently warmer-than-average; an ingredient important for the development and sustainability of hurricanes. Finally, El Nino, an abnormal warming of surface ocean waters in the eastern tropical Pacific, shows no sign of development through this summer and autumn. There is evidence to show that during El Nino events, hurricane activity is suppressed.

    Despite such predictions, it is still too difficult to forecast so far in advance, when exactly a hurricane will form and what path it will take; only short-range forecasts are able to do this, bu often to a high degree of accuracy. For those living close to the Atlantic Basin, in the path of tropical storms and hurricanes, such short-range forecasts may well prove a life-saver in what looks set to be an active hurricane season during 2013.

    By: Gareth Harvey