RMS has released its 2017 North Atlantic Hurricane Season Review documenting one of the most active, damaging, and costliest seasons on record. The 2017 season saw a total of 17 named storms, with ten of these storms reaching hurricane strength and occurring consecutively within a hyperactive period between August and October. The season will be remembered for its six major hurricanes and specifically for the impacts of three of these storms: Harvey, Irma, and Maria.
Although my colleague Peter Holland declared the Atlantic hurricane season officially closed, there are reports in the media that environmental conditions in the North Atlantic basin may be favorable enough to sustain tropical cyclones, potentially adding to what has already been a very active year and perhaps foretelling an early start to hurricane activity in 2018.
The official hurricane season for the North Atlantic runs from June 1 to November 30 and encompasses over 97 percent of annual climatological activity. Out-of-season tropical systems — events happening through December to May — are rare, but not unprecedented. The U.S. National Oceanic and Atmospheric Administration (NOAA) Hurricane Research Division (HRD) states that since 1851, 88 storms have been observed in the Atlantic during the off-season — that’s about one out-of-season storm every two years. In theory, this could be an underestimate, as the peer-reviewed literature suggests an undercount of Atlantic tropical cyclones prior to the satellite reconnaissance era.
The midway point of the Atlantic hurricane season has just passed, and despite a relatively tame start, we have already witnessed two major U.S. hurricane landfalls — Harvey and Irma — in quick succession. It is the first calendar year on record where two hurricanes of Category 4 strength or greater have made landfall in the contiguous U.S. To add insult to injury, Maria has quickly intensified and is expected to be the fourth major hurricane of the season as it tracks through the Leeward Islands, an area left devastated by Irma less than two weeks ago.
With 13 named storms, seven hurricanes, and three major hurricanes, we have already met the National Oceanic and Atmospheric Administration (NOAA) definition of an above-average full Atlantic hurricane season. It is understandable that many in the insurance industry may be suffering from “hurricane fatigue” well before the calendar flips over to October.
If we’ve learned anything about forecasts and predictions (pick any recent event, sporting, political etc.) they give an indication of the situation, but cannot predict the absolute outcome, and surprises can most definitely happen. We are into the first weeks of the North Atlantic hurricane season, which officially runs for six months from June 1 to November 30, and a variety of forecasting groups and agencies have issued preseason forecasts. Continue reading