~ ‘Strong likelihood’ El Niño will form’ ~
MIAMI--The 2012 Atlantic hurricane season will be “below average” with ten tropical storms, four of which will strengthen into hurricanes, Colorado State University (CSU) forecasters predicted on Wednesday.
Two of those will become major hurricanes with winds of at least 111 miles per hour (178 kph), the team founded by forecasting pioneer William Gray said. In an average year, there are 11 tropical storms, six hurricanes and two major hurricanes in the Atlantic, Caribbean and Gulf of Mexico, during the season that runs from June 1 to November 30.
The outlook for a milder 2012 season was based on two main factors: hurricanes thrive on warm water and the tropical Atlantic has cooled this year, the researchers said. There is also a “fairly high” likelihood that an El Niño effect will develop this summer, they added.
El Niño is a warming of surface waters in the tropical Pacific that occurs every four to 12 years and has far-ranging effects around the world. It creates wind shear that makes it harder for nascent storms to grow into hurricanes, in the Atlantic-Caribbean basin. But it can produce drought and crop failure in parts of South Asia and wetter-than-normal conditions in western coastal areas of South America.
Despite the forecast for a moderate number of storms, Phil Klotzbach of the CSU Tropical Meteorology Project said vulnerable coastal residents should take the same hurricane preparations they do every year. “Regardless of how active or inactive the seasonal forecast is, it takes only one landfall event near you to make this an active season,” he said.
There is a 42-per-cent chance that a major hurricane will hit the US coast this year, compared with an historical average of 52 per cent, the researchers said. The forecasters said there was a 24-per-cent chance a major hurricane would hit the US East Coast, compared with an historical average of 31 per cent, and a 24-per-cent chance that one would hit the Gulf of Mexico coast, compared with an average of 30 per cent.
Weather watchers may notice a few small changes when theNationalHurricaneCenterbegins issuing its advisories this year. Forecasters made small tweaks to the Saffir-Simpson scale of hurricane intensity, to fix a longstanding problem that arises from rounding.
The scale divides hurricanes into five categories based on wind speed, measured in 5-knot increments. For public advisories, knots are converted to miles per hour (mph) and kilometres per hour (kph), rounded to the nearest 5mph or 5kph. That created problems when storms neared the threshold dividing the categories. Because of rounding, it was possible for a storm to fall into Category 4 when measured in knots, and Category 3 when measured in mph or kph.
To fix that, small adjustments in thresholds were made to Categories 3 through 5, while Categories 1 and 2 were left unchanged. The change takes effect on May 15 and does not affect categories assigned to hurricanes that occurred previously.
The new scale is Category 1: 74-95mph (64-82 knots, 119-153kph), Category 2: 96-110mph (83-95 knots, 154-177kph), Category 3: 111-129mph (96-112 knots, 178-208kph), Category 4: 130-156mph (113-136 knots, 209-251kph), Category 5: 157mph or higher (137 knots or higher, 252kph or higher).
Local government Financial Services Authority (FSA) David Beckham Sweden Simon Cowell Lake District
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