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000 NOUS41 KBOX 181305 PNSBOX CTZ002>004-MAZ002>024-026-RIZ001>008-181715- Public Information Statement National Weather Service Taunton MA 905 AM EDT Tue Jul 18 2017 ...Hurricane Preparedness Week in Southern New England... ...Rules of Thumb For Southern New England Hurricanes - Part 2... The National Weather Service has declared this week as hurricane preparedness week in southern New England. The following is the second in a series of five statements, the first three with rules of thumb for New England hurricanes and the last two with preparedness actions. Yesterday we discussed the fact that you should not concentrate on when the eye is forecast to make landfall, since the important impacts of the storm occur way out in advance of the eye. Also any named tropical cyclone in the Bahamas should have your attention. The third rule of thumb is that you need to know where you are with respect to the expected track of the eye in order to determine your most likely hazards. Generally expect flooding rainfall to the left of the track. To the right of the track, damaging winds and storm surge inundation are the most likely threats. This is not to say no other hazards will exist, merely these are the most likely threats. It is imperative you do not focus on the exact track as the impacts will be felt many miles away from the track of the eye. In the textbooks, hurricanes are perfectly symmetric. As the tropical cyclone approaches, the rain and wind pound from one direction, then the eye moves overhead and it is calm, then the rain and wind pound equally as hard but from the opposite direction. This scenario is true of storms at lower latitudes. However, hurricanes that affect southern New England are typically accelerating up the coast and becoming asymmetric. This is because most of them are in the process of transitioning from a purely tropical system to the structure almost like that of a winter storm. As a result, flooding rains tend to occur to the north and west of the track of the eye. Partial sunshine occurs with only scattered showers to the south and east of the eye. But that is where the powerful winds are, and where the storm surge is maximized. After the eye moves through, most of the rain is over. In terms of rain there is no second half. The winds do shift directions and can be briefly strong on the back side. To illustrate this rule, take Hurricane Bob from August of 1991. It tracked northeast across southeastern Massachusetts. Less than one-half inch of rain occurred during the entire hurricane across Cape Cod, to the right of the track. Six to seven inches of flooding rainfall occurred over Foster/Glocester Rhode Island, to the immediate left of the track. The strongest winds and highest storm surge, however, occurred over Cape Cod and the islands where gusts up to 125 mph occurred. Irene in 2011 also exhibited this behavior, with devastating rainfall to the left of the storm track across most of the East Coast. The stronger winds were across Connecticut, Rhode Island and portions southeast Massachusetts, which were to the right of the track. In 1955, Tropical Storm Diane took an unusual track. It paralleled the south coast of New England, which put all of southern New England on the rainy north and west side of the storm. A foot of rain was common across a large portion of interior southern New England, with the jackpot over Westfield Massachusetts, where 18.15 inches of rain occurred in just 24 hours. As with any rules of thumb, there can be exceptions, but they are rather rare. One notable exception was Hurricane Carol in 1954 which had the heaviest rains just to the right of the track. Stay tuned tomorrow for more rules of thumb for New England hurricanes. $$ For the latest updates...please visit our webpage at You can follow us on Facebook at You can follow us on Twitter at @NWSBoston is the U.S. government's official web portal to all federal, state and local government web resources and services.