TT Talk - Above-normal hurricane season anticipated this year.
President Obama issued a proclamation on 20 May announcing 'National Hurricane Preparedness Week', 22-28 May 2011. As the proclamation noted, 'Hurricanes are powerful storms that can create severe flooding, dangerous storm surges, high winds, and tornadoes.
The effects of these storms can be devastating to entire communities and can have long-lasting consequences, including loss of life and property. In addition to threatening coastal areas, hurricanes significantly impact inland locations'.
Some parts of the US will need no reminder of the devastation that can be caused, following the high incidence of tornadoes through the South and large degree of flooding. And it is important to remember that apart from the specific impact of wind, hurricanes often cause storm surge and lead to substantial inland flooding.
The National Hurricane Centre of NOAA (the National Oceanic and Atmospheric Administration) has advised that the key climatic factors this season are (quoting):
The continuing high activity era Since 1995, the tropical multi-decadal signal has brought ocean and atmospheric conditions conducive for development in sync, leading to more active Atlantic hurricane seasons.
Warm Atlantic Ocean water. Sea surface temperatures where storms often develop and move across the Atlantic are up to two degrees Fahrenheit warmer-than-average.
La Niña which continues to weaken in the equatorial Pacific Ocean, is expected to dissipate in May or June, but its impacts such as reduced wind shear are expected to continue into the hurricane season.
The conclusion is a forecast of an above-normal hurricane season this year.
NOAA does not make an 'official' seasonal hurricane landfall outlook. However Tropical Storm Risk forecast US landfalling tropical cyclone activity in 2011 to be about 25% above the 1950-2010 norm. Thus, while forecasters are not always going to be right, and both 2009 and 2010 were relatively benign, it certainly is time to prepare carefully.
The last hurricane to strike the US was 'Hurricane Ike' in 2008. In 2009 and 2010 only tropical strength storms struck the US. Last year there were 19 such storms, the third most on record. The US has not had a three year stretch without a hurricane landfall since the 1860's.
The TT Club strongly recommends that coastal and inland facilities, particularly those located along the Atlantic seaboard and the Gulf of Mexico, review and update their hurricane safety procedures to ensure all staff are familiar with the protocol.
In 2009, the Club published the second edition of its handbook on this subject, 'WindStorm II Practical Risk Management Guidance for Marine & Inland Terminals', which is filled with valuable information to minimise the losses incurred, including guidance on creating an emergency plan and easy-to-use checklists. This handbook is available in both PDF and print form. It's free of charge to TT Club Members and at a cost of £36 to anyone else.
Recognising that this article is specific to the Americas, it also serves as a reminder to those in other parts of the world, whether within the tropics or not. Winds gusting up to hurricane strength (Beaufort force 12 or 32.7 m/s) are not restricted to latitude, proximity to the coast or the season. The time to consider exposure to such risks is always in advance; preparation is key!