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First Atlantic tropical depression forming?

By: Dr. Jeff Masters,

Take a look at the gathering clouds over the western Caribbean Sea, just north of Honduras. All the ingredients are in place for the first tropical depression of the season to form--surface pressures are starting to fall, upper level winds are creating a favorable outflow pattern of high cirrus clouds, and there is low vertical wind shear and warm 87 degree Fahrenheit water. I'd estimate that Western Caribbean systems at this stage of organization this time of year form into tropical depressions about 30% of the time. It is not well understood why so many of these type of systems fail to form into tropical depressions when all the ingedients needed are seemingly in place; this is an area of intensive research.

If a tropical depression does form, the GFS computer model predicts it will move north into the Gulf of Mexico and possibly threaten the U.S. Gulf Coast. However, this computer model is very unreliable at predicting the motion of tropical systems that haven't formed yet. For the most reliable information on developing tropical systems, read the National Hurricane Center's
Tropical Weather Outlook
, which is updated daily at 11am, 5pm, 11pm, and 5am EDT during hurricane season.

Dr. Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.