One new weak disturbance mid-Atlantic

General overview 1400z 22nd August 2013

Disturbance thirty five is now in the western Caribbean and about a day's run to the east of Nicaragua as is moves west at 13 knots. This is expected to move ashore in the next 24 hours and dissipate. Unusually, US Navy modellers - normally noted for conservative forecasting - have this turning sharp right tonight and then crossing the Yucatan peninsular and into the Bay of Campeche, where conditions are favourable for development into a weak cyclone before landing in southern Mexico. This is not a widely held view.

For the sake of maintaining numerical order, we report on a new disturbance - designated thirty seven – in the north central sub-tropical Atlantic and already headed north. If this does develop, it will have no impact on our area of interest or indeed any land area.

Disturbance thirty-six continues coughing and spluttering in suffocating dry air in the east-central Atlantic. This is on its last legs.

The next tropical wave is likely to emerge off the African coast within the next 24 hours, but a little to the north of the normal latitude. Rising air is confined to a range of latitudes to the south of the intertropical convergence zone - the westbound conveyor belt between African and the Caribbean, if you like. Since disturbances currently leaving the African coast are tracking to the north of this, they do not benefit from convection and are failing to develop.

Stand easy