Mid-way into the Atlantic Hurricane Season, US forecasters are now revising forecasts to suggest an even higher likelihood of a below-normal season.
Back in May, the National Oceanic and Atmospheric Administration said there was a 70 per cent chance of a quiet hurricane season but now it says that chance has risen to a nine in 10 possibility.
Gerry Bell – the lead seasonal hurricane forecaster, however, once again urged caution noting that the peak months of the season were now here and even a single storm could cause huge damage
Two tropical storms already have struck the US this year. Ana made landfall in South Carolina in May, and Bill made landfall in Texas, in June.
The 90 percent probability of a below-normal season is the highest confidence level given by NOAA since seasonal hurricane outlooks began in 1998.
The updated outlook also lowers the overall expected storm activity this season. The outlook now includes a 70 percent chance of 6-10 named storms (from 6-11 in the initial May Outlook), of which 1-4 will become hurricanes (from 3-6 in May), and 0-1 will become major hurricanes (from 0-2 in May).
These ranges — which include the three named storms to-date (Ana, Bill, and Claudette) — are centered well below the seasonal averages of 12 named storms, six hurricanes and three major hurricanes.
Forecasters attribute the high likelihood of a below-normal season to three primary factors: That El Niño has strengthened as predicted; that conditions associated with El Nino have strengthened; and Tropical Atlantic sea-surface temperatures are predicted to remain below average and much cooler than the rest of the global tropics.
The Atlantic hurricane season runs from June 1 through November 30.