ERIKA shaping up for Florida

General overview Wednesday 26th August 2015

The remains of DANNY have all but dissipated over Hispaniola, leaving just a waterlogged low pressure system which is tracking west but has no organisation to it and will not redevelop. This did not pass unnoticed across the Virgin Islands and Puerto Rico, and will also make its presence felt as it passes the Dominican Republic and Haiti depositing rainfall in Biblical quantities, or what we refer to in London as ‘summer'.

All eyes on tropical storm ERIKA of course. As we explained yesterday, a reckless groundspeed, a track across a patch of dry air and a brief encounter with upper level shear was to impact on the cyclone's surface and vertical structure, making reliable forecasting something of a guessing game. ERIKA has passed that stage, is intensifying and there is now a limited degree of certainty to track. Currently 200 miles east of the Leeward Islands, the storm is headed west-nor'west at 15 knots with winds of 45 gusting 55 knots over a windfield radius of 40 miles. The current hurricane severity index is 3 out of a possible 50 points (1 size, 2 intensity). There are three tracks being discussed. First, we can say with almost complete certainty that this won't make the western side of the Gulf of Mexico but the further west it does track, the weaker it will be. A couple of US modellers and the Canadian guy have ERIKA tracking along the west coast of Florida and landing south of Tallahassee. Considering the Canadian chap has had the success rate of a blind sniper in recent years, I'd suggest this is not a hot favourite. To the extreme east some of the older modelling systems - still with a degree of accuracy - have ERIKA reaching hurricane strength east of the Bahamas then curving east into the Atlantic. We'd would all prefer that one. Unfortunately, the more reliable European and US modellers seem to be in agreement. ERIKA will intensify to hurricane strength by Sunday evening as it crosses the Bahamas and make a landfall close to Miami on Monday morning. The reliable US agencies are going as far as to recommend that hurricane response plans for the Florida peninsula south and east of a line between Daytona Beach and St Petersburg are put into effect now. We think there is still a chance of weakening if ERIKA passes close to or over Puerto Rico and Hispaniola, but it's a long shot.

Disturbance thirty two is almost mid-Atlantic now and is moving west at 12 knots. This is a little north of track which is drawing Saharan air into the surface array and will restrict any chances of this becoming a tropical depression. It is entirely likely that this will remain a weak disturbance and will not significantly impact any land areas.

Stand easy, for now.