From Weather Underground (also on blogroll at right as Wunderblog during the season):
The 2019 Atlantic Hurricane Season Begins; 91L in Gulf of Mexico a Threat to Develop
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....June is typically inactive in the Atlantic, with about one named storm forming every two years, on average. The usual location for June storms to form is in the Gulf of Mexico, Western Caribbean, or the waters between The Bahamas and Bermuda, several hundred miles east of the Southeast U.S. coast, where sea surface temperatures (SSTs) are warmest. SSTs are nearly always too cold in June to allow storms to develop between the coast of Africa and the Lesser Antilles Islands. There have only been three such developments in the historical record—Tropical Storm Ana of 1979, Tropical Storm Bret of 2017, and an unnamed hurricane in 1933.
June storms often form when a cold front moves off the U.S. coast and stalls out, with the old frontal boundary serving as a focal point for development of a tropical disturbance. Another way to get Atlantic June storms is for a disturbed weather area in the Eastern Pacific Intertropical Convergence Zone (ITCZ) to push north into the Western Caribbean and spawn a storm there. This was the case for Tropical Storm Alberto of 2006 (which may have also had help from an African tropical wave). June storms often form from Central American Gyres, like 91L is poised to do.
African tropical waves, which serve as the instigators of about 85% of all major hurricanes, are usually too infrequent and too far south in June to trigger tropical storm formation. Occasionally, a tropical wave tracks far enough to the north to act as a seed for a June storm in the Western Caribbean or southern Gulf of Mexico. This was the case for the strongest and deadliest June hurricane on record, Hurricane Audrey of 1957. Audrey formed from an African tropical wave on June 24, 1957 in the southern Gulf of Mexico’s Bay of Campeche. The rapidly intensifying storm struck the Louisiana/Texas border region as a Category 3 storm with 125 mph winds, tying it with Hurricane Alex of 2010 as the strongest June hurricane on record. Audrey killed over 400 people in Louisiana and Texas.
....MUCH MORE
Figure 2. Radar image of Hurricane Audrey on June 27, 1957, a few hours before landfall. Image credit: US Air Force/NOAA. Majority of forecasters predicting a near-average Atlantic hurricane season
As detailed in our May 23 post, the majority of the best-regarded pre-season Atlantic forecasts are predicting a near-average hurricane season. Since then, one major player, TSR, has put out an update to their forecast, calling for slightly more activity than their April 5 forecast (see below). The next major forecast update to watch occurs on Tuesday June 5, when Colorado State University (CSU) issues their widely-watched forecast....
*Re/Insurance: With Today's Start of the Official Hurricane Season, A Look At Various Forecasts
