Arlene Develops in the Atlantic
While the Atlantic Hurricane Season doesn’t officially start until June 1st, the 2017 Atlantic Hurricane season is off to an early start! Last week, Tropical Storm ARLENE became only the second named storm to develop in the month of April in the satellite era (since the mid-1960s)! The other storm only to ever develop in April was that of Ana in 2003, which developed became a named storm on the same day as Arlene, April 20th!
(NOAA: Satellite image of Tropical Storm Arlene on April 20, 2017)
Unusual Storm; Trending Early?
Arlene was definitely an usual storm, developing more than 1 month ahead of the official start to the Atlantic hurricane season, June 1st. Interestingly, this is the 3rd consecutive year that a system has developed before June 1st. Last year, an extremely rare and “remarkable” Hurricane Alex formed on January 13, 2016 and Tropical Storm Bonnie formed on May 28th, which made landfall in South Carolina on May 29th. In 2015, Tropical Storm Ana developed on May 8th. Note that storms early in the year tend to be weaker due to water temperatures being cooler in the Atlantic, but with water temperatures trending warmer in recent years, tropical systems have been developing earlier than normal.
(NOAA: Hurricane Alex at peak intensity and approaching the Azores on January 14, 2016)
Early Look At the 2017 Hurricane Season
Despite the early start to the 2017 Atlantic Hurricane Season, Colorado State University is forecasting a slightly below average season this year. Here’s a look at the numbers, which was released on Thursday, April 6th:
Named Storms: Forecast (11) – Average (12)
Hurricanes: Forecast (4) – Average (6-7)
Major Hurricanes: Forecast (2) – Average (2)
The reasoning behind the slightly below average hurricane forecast is due to the development of a weak to moderate El Nino likely developing in the Pacific Basin (According to NOAA). When an El Nino develops, wind shear in the middle and upper levels of the atmosphere increases in the Atlantic, which leads to less favorable weather conditions for tropical development there. There is also some assumption by forecasters that water temperatures in the Atlantic will be trending cooler than average this year, which will may also help to keep tropical formation lower.
With that said, NOAA reminds us that “it only takes one storm to change of life and community.” Despite a slightly below average hurricane season being forecast, make sure you are and will be prepared when and if tropical weather threatens. Here are some safety tips as we get closer to the tropical season.
“It only takes one storm to change your life and community. Tropical cyclones are among nature’s most powerful and destructive phenomena. If you live in an area prone to tropical cyclones, you need to be prepared. Even areas well away from the coastline can be threatened by dangerous flooding, destructive winds and tornadoes from these storms. The National Hurricane Center and the Central Pacific Hurricane Center issue watches, warnings, forecasts, and analyses of hazardous tropical weather. Hurricane Preparedness Week (May 7-13, 2017) is your time to prepare for a potential land-falling tropical storm or hurricane. Learn how with the daily tips below and related links. Share these with your friends and family to ensure that they’re prepared.”
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