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Weekly Weather Event -Week of September 14th

September 18, 2020

On Thursday September 17th, tropical depression 22 in the Gulf of Mexico was slated to become Tropical Storm Wilfred, taking up the last name in the official list of Atlantic storms for the 2020 year. Instead, in the span of 12 hours, Tropical Storm Wilfred formed in the eastern Atlantic Ocean, and Subtropical Storm Alpha began moving into Portugal. Should tropical depression 22 develop into a tropical storm, will be named Beta. This is the first time since 2005 and the second time in its history that the National Hurricane Center has needed to dip into the Greek alphabet for the hurricane season.

September is the busiest month for hurricanes and tropical storms, with September 10th the statistically most likely day of the year for there to be a tropical cyclone in the Atlantic basin. This is due to minimum wind shear within the Atlantic by late August combined with warm summer waters. If 2020 follows the pattern of a typical hurricane season after the peak, we would expect to see named storms through Eta or Theta, tying or surpassing the 2005 season at 28 named storms. Should 2020 follow a pattern similar to 2005, where there were an additional 11 named storms after the September 10th peak, we instead could see named storms all the way through Nu, bringing the total to 34.

This busier than average season also raises an important question: what happens if a storm with a Greek letter reaches the point where it would normally be retired? Officially, the World Meteorological Organization has stated that the agency will not retire a Greek letter in this situation, instead noting it alongside other retired names but keeping the letter in circulation for later years.