Despite the fact that July was a very quiet month in the Atlantic for tropical systems and that overall this tropical season could turn out to have below-normal activity, there are reasons to believe that the east coast is vulnerable to an impact by a hurricane. In many ways, the current large-scale weather pattern resembles the decade of the 1950’s when, for example, there were colder-than-normal sea surface temperatures in the northern Pacific Ocean and warmer-than-normal temperatures in the Atlantic Ocean. This is the same pattern that we have right now since we flipped into a cold phase in the northern Pacific Ocean a couple of years ago, and the warmer-than-normal cycle of the Atlantic Ocean during the past several years has another few years to run. In fact, the current severe drought that we are experiencing in much of the mid-section of the country resembles drought conditions that were last experienced in the 1950’s in much of the same area which coincidentally was shortly after the last long-term flip in the northern Pacific Ocean sea surface temperature cycle.
One of the other notable weather characteristics of the 1950’s was that the east coast was actually affected quite frequently by hurricanes (e.g., Hazel and Carol in 1954; Connie and Diane in 1955). In fact, seven major hurricanes impacted the east coast of the U.S. between 1954 and 1960. Hurricane Irene, which impacted much of the east coast late last August, may have been a warning that a repeat of the 1950’s pattern has begun. We’ll continue to monitor the situation for the remainder of this tropical season which climatologically should ramp up over the next several weeks towards a peak around the middle of September.