No pre-season tropical storms in the Atlantic due to 3 factors that will soon disappear
Pre-season tropical storms have developed in the Atlantic in April or May during eight of the last 10 years but not this year. With a blockbuster season expected due in part to unusually high ocean temperatures, why haven't there been any storms yet?
AccuWeather Lead Hurricane Forecaster Alex DaSilva says there are three main reasons why hurricane season hasn't kicked off early this year, but once they are removed from the equation, the season may hit the ground running.
Most pre- and early-season storms form in the Gulf of Mexico or Caribbean. One factor has been the atmospheric pattern, with a dip in the jet stream over the West Coast and a "heat dome" over Mexico and Texas, cold fronts or low pressure systems aren't able to move into the Gulf of Mexico or beyond. Without that, tropical storms won't form.
Second, DaSilva says, is wind shear. "Vertical wind shear has been higher than the historical average, especially in the Caribbean. Vertical wind shear typically keeps tropical storms from forming in May, and a pre-season storm can only develop in wind shear that is below average," DaSilva explained.
The heat dome has also exacerbated the drought in Mexico, leading to above-normal numbers of wildfires, which have sent dry, smoky air across the Gulf of Mexico. Smoke and dry air keep tropical storms from forming.
As we move forward in June, all of these factors should decrease, paving the way to a super-charged Atlantic hurricane season.