Two new disturbances and a chance in pressure gradients in the US Gulf.
Overview Monday 10th August 2015
Disturbance twenty four has developed a day or two east of the Leeward Islands and is moving west at 12 knots. The disturbance is producing disorganised showers and thunderstorms that could bring gusty winds and brief heavy rainfall to the Windward Islands and Trinidad and Tobago tomorrow and Wednesday, however conditions in the Caribbean are hostile and development chances are low. This is set to change though. A high pressure area has sat tight over the south-western United States for some time, causing blue skies, high temperatures and dry sinking air across the region and the Gulf of Mexico. This is set to change as the high moves west, and the low pressure area over the mid-latitude eastern seaboard will be dragged south and west towards the Gulf. Moist, rising air will provide a sweet environment for tropical depression development late this week and early next. There are no identifiable contenders headed for the region, except a slim chance of disturbance twenty four if it can get past the doorman of upper level shear in the southern Caribbean perhaps.
Disturbance twenty five has crossed the African coast and is moving west at 12 knots. This has emerged from Mauretania, which is a little north of the usual source and may indicate an early turn into the sub-tropical Atlantic. While this is currently producing showers and thunderstorms, it is headed from dry air where conditions are not favourable for development.
Outside of the two disturbances, conditions across the entire region are very calm creating conditions which would have been perilous for the old sailing ship men, when days and weeks in the doldrums would pass without a puff of wind and water would be rationed.