Active Atlantic Hurricane Season Predicted
The 2013 Atlantic hurricane season, which lasts from 1 June to 30 November, is expected to be active because of a combination of climate factors.
The U.S. National Oceanic and Atmospheric Administration’s Climate Prediction Center forecast a 70 percent likelihood of 13 to 20 named storms (winds of 63 kilometers per hour/39 miles per hour or higher), of which 7 to 11 could become hurricanes (winds of 119 kmh/74 mph or higher), including 3 to 6 major hurricanes (Category 3, 4 or 5; winds of 178 kph/ 111 mph or higher).
These ranges are well above the seasonal average of 12 named storms, 6 hurricanes and 3 major hurricanes.
WMO fact sheet on tropical cyclones and hurricanes
NOAA’s Hurricane Season Outlook says that three climate factors that strongly control Atlantic hurricane activity are expected to come together to produce an active or extremely active 2013 hurricane season. These are:
- A continuation of the atmospheric climate pattern, which includes a strong west African monsoon, that is responsible for the ongoing era of high activity for Atlantic hurricanes that began in 1995;
- Warmer-than-average water temperatures in the tropical Atlantic Ocean and Caribbean Sea; and
- El Niño is not expected to develop and suppress hurricane formation.
NOAA’s seasonal hurricane outlook is not a hurricane landfall forecast; it does not predict how many storms will hit land or where a storm will strike. Forecasts for individual storms and their impacts will be provided throughout the season by NOAA’s National Hurricane Center, which acts as a Regional Specialized Meteorological Centre of WMO.
The first named storm of the season will be Andrea followed by Barry, according to WMO’s list of hurricane names, which is intended to make it easier for people to understand and recognize tropical cyclones and be aware of the risks. The list of names, agreed by WMO’s Hurricane Committee, rotates every six years. If a storm is so deadly or costly that the future use of its name would be inappropriate, then it is retired and an alternative name is chosen.Thus at its meeting in April 2013, the WMO Hurricane Committee retired the name Sandy (which will be replaced by Sara in 2018).
Fact sheet on tropical cyclone names.
At its April meeting, the WMO Hurricane Committee adopted a proposal from the U.S. National Hurricane Center to broaden hurricane and tropical storm watch and warning definitions to allow these watches and warnings to remain in effect after a tropical cyclone becomes post-tropical, when such a storm poses a significant threat to life and property. RSMC Miami will ensure a continuity of service by continuing to issue advisories during the post-tropical stage, when a storm poses a significant threat to life and property.
These changes, which will take immediate effect, were motivated by the special challenges posed by Hurricane Sandy, which evolved from a hurricane to a post-tropical cyclone prior to reaching the coast of the United States of America.
NOAA’s outlook for the Eastern Pacific basin is for a below-normal hurricane season and the Central Pacific basin is also expected to have a below-normal season. NOAA will issue an updated outlook for the Atlantic hurricane season in early August, just prior to the historical peak of the season.