Confused Independence Day skies preventing cyclonic development
General situation 1400Z 4th July 2013
By the dawn's early light this Independence Day, the skies over the Gulf of Mexico showed a confused pressure map. All three systems are now interacting and producing strong upper level shear over the northern latitudes of the US Gulf.
In the west, disturbance ten (which proudly we hailed seven days before it was formally recognised) is loafing around in the central Bay of Campeche and likely to continue to cause widespread showers and thunderstorms to much of the central and eastern Gulf of Mexico through the weekend. This system has the only chance of developing if, by the weekend, the trough weakens moves leaving a keyhole of undisturbed moist air over lush warm water, however this may be too little too late and we would expect the system to run ashore in the vicinity of Port Arthur and Lake Charles.
Disturbance twelve has opened up to a low pressure wave which extends from southern Alabama to just north of the Yucatan peninsula, moving north-west 15 knots. This is losing the perilous fight for survival as it meets the frontal system which is still tracing the Gulf coast, producing widespread showers and thunderstorms across the northern and eastern Gulf of Mexico. This cannot now develop but will bring potentially heavy rainfall to much of the Gulf Coast and southern continental United States and cause some brisk squalls across much of the Gulf of Mexico this weekend.
The curved ball disturbance fourteen has peeled away from the high pressure ridge and started moving west. There is some chatter that this could move into the Gulf of Mexico and develop further however the current upper level mess in the Gulf is producing gallantly streaming upper level shear which may arrest any development.
Disturbance thirteen mid-Atlantic continues to drift away from the convergence zone and in the next day or so, may have its last gleaming.
Have a nice day.