17th big Atlantic storm takes shape in busy season

The 17th storm large enough to earn its own name has formed in the Atlantic Ocean, making Tropical Storm Rina the latest in an already above-average hurricane season, forecasters said Tuesday.

As of 1500 GMT, Rina posed no threat to land, and was churning in the open Atlantic 905 miles (1,455 kilometers) east of Bermuda, the Miami-based National Hurricane Center said.With maximum sustained winds of 40 miles per hour (65 kilometers), the storm was headed in a northeasterly direction, moving at a speed of 12 miles per hour (19 kilometers per hour).

This season was expected to be above average, with 11 to 17 named storms anticipated at the outset, a figure forecasters revised upward to 14-19 in August.
In an update posted on November 1, the NHC said 2017 so far has been " above average" in terms of the number of storm activity, compared to the 1981-2010 average.
Normally there are about 12 named storms -- of which six become hurricanes -- per year in the Atlantic. With devastating storms like Harvey, Irma, and Maria, this has been the busiest Atlantic hurricane season since 2005, when there were 28 named storms, which includes tropical storms and hurricanes.

factors that make way for more storms include an ocean that is one to two degrees Fahrenheit warmer than average, increasing moisture in the tropical air, a weaker wind shear across the tropical Atlantic and Caribbean, and stronger wind patterns off Africa which more easily whip up storms, according to NHC lead forecaster Gerry Bell. The season officially runs from June 1 to November 30.