Recapping the Updated 2015 Hurricane Predictions

By Vernon Trollinger, September 1, 2015, Hurricane Prep, News

Recapping the Updated 2015 Hurricane PredictionsBack on August 6, 2015, the National Oceanic and Atmospheric Administration (NOAA) released its updated prediction for this year’s Atlantic hurricane season. Not surprisingly, it announced it was 90% sure this year would be another below-normal season.

May’s hurricane predictions called for 6 to 11 named tropical storms, 3 to 6 of which would grow to category 1 or 2 hurricanes, and of those perhaps 2 would become major hurricanes (category 3-5).

NOAA’s revised forecast lowers the numbers:

  • 6-10 named tropical storms
  • 1-4 category 1 or 2 hurricanes
  • 1 major hurricane.

As with their earlier prediction, NOAA cites the emerging El Nino phenomena as creating global weather patterns that disrupt the hurricane formation in the Atlantic Ocean. While this El Niño dawdled all winter before fully emerging this spring, it is expected to be one the strongest ones on record and exert its peak effects on temperature and precipitation during the coming  late fall or early winter.

Recent Storm History

So far this year, there have been only 4 tropical storms in the Atlantic (Ana, Bill, Claudette, and Erika) and only one hurricane (Danny). Tropical Storm Ana came ashore in South Carolina on May 10, while Bill landed near Houston, TX on June 16. Claudette formed on July 13 in the Atlantic Ocean 500 miles away from the US coast and dispersed 48 hours later.

Interestingly, observations made from both Hurricane Danny and Tropical Storm Erika show the effects of El Niño at work.

Hurricane Danny evolved from a tropical depression to tropical storm on August 18. It struggled to remain intact against a persistent mid-oceanic trough across the Caribbean region, strengthening to become a Category 1 Hurricane on August 20. By the next day, however, the hurricane eye disappeared as wind shear with drier air began wearing down the storm system. Danny weakened for the next 48 hours and on August 22, it was downgraded to a tropical storm. Wind shearing continued to pull the storm apart during August 23. By the end of the next day, August 24, Danny dissipated just west of the island of Guadalupe on the Leeward Islands.

Tropical Storm Erika began organizing a little further west of where Danny started and has followed a similar track. As of this writing (08/29/2015), NOAA reported the storm had strengthened overnight, but faces wind shear problems due to an upper-level trough. While bringing 2-4 inches of rain to the northeast Caribbean, Erika remains poorly organized. If the storm survives the next 48 hours, it is expected to strengthen with the aid of a more favorable wind pattern as it passes over warmer waters.

El Niño Effects

While an El Niño phenomenon come about due to warm water in the Pacific Ocean, their warm water affects wind circulation patterns worldwide (known as the “Walker Circulation”). Tropical storms and hurricanes develop in the calm, warm waters. For Atlantic hurricanes, the calm, warm waters off the west coast of Africa are perfect hurricane nurseries. Storm systems swirl, build, and blow westward to the calm and sometimes warmer Caribbean. El Niños, however, add vertical wind shearing in the Caribbean, and this disrupts and dissipates the heat energy that builds storms. Not only do El Niños inhibit hurricane formation, they also can dispel those storm systems that do form.

All the same, it is still hurricane season, and we’re just now entering the peak of the season. With this week marking the 10-year anniversary of Hurricane Katrina, it’s a pointed reminder that any storm has the potential to be dangerous, and it’s vital to stay prepared. Follow us on TwitterFacebook, and Hurricane Prep Center for key information about what’s happening in your area when a hurricane strikes.

Be Sociable, Share!

Related Posts

Tags: , , , , , ,

Comments are closed.