Hurricane Maria went through a phase of explosive intensification, dropping over 20mb pressure in a few hours, shortly before making landfall on Dominica as a compact but intense category 5 hurricane. The size and structure of the storm at landfall was very similar to Hurricane Andrew at landfall in South Florida in 1992, although at least officialy Maria was not quite as intense. We may never know precisely how intense the inner eyewall was at landfall since, like Andrew, it was an exceptionally tight feature.
The storm’s structure was somewhat disrupted by the moderately high mountains on the island and it declined to category 4 at it crossed and emerged into the Caribbean. However, it has quickly recovered and as of the 8 am intermediate advisory Maria is once again a category 5 hurricane with sustained winds of 160 mph and a minimum central pressure of 933mb.
Some variation in intensity is likely over the next couple of days. The official forecast is that Maria will be an upper end category 4 as it passes near or over the US Virgin Islands and Puerto Rico. But it could just as easily be a strong category 5. We simply don’t have the skill to forecast intensity with any great precision.
Reports out of Dominica are sparse, but it appears there has been the kind of devastating damage one would expect from such an intense storm. Search and rescue operations are underway. I will update this diary with any significant news regarding damage, injury or possible loss of life.
The neighboring islands of Guadeloupe and Martinique did see tropical storm force winds, but I have not seen any reliable reports of sustained hurricane force. This is due to the very compact nature of Maria as it passed through the island chain.
Model guidance is very tightly clustered in taking Maria over or very near St. Croix in the US Virgin Islands and then Puerto Rico. This is an emergency situation for these islands. The nearest thing in relatively recent history would be Hurricane Hugo in 1989, which was a devastating blow to those islands. But Maria will in all likelihood be significantly worse. The Virgin Islands suffered a major blow from Hurricane Irma and are only in the early stages of recovery from that. A storm like this coming when buildings and infrastructure are already damaged and piles of debris are everywhere has more than the usual potential to be deadly.
Puerto Rico did not see a direct impact from Irma but nonetheless suffered significant damage to infrastructure, particularly the power grid. That makes them even more vulnerable than usual to damage from a direct impact of a major hurricane.
Beyond Puerto Rico, the Dominican Republic is likely to see a major rain/flooding event in its eastern districts but probably not a direct impact. The Turks and Caicos islands, which were directly hit by Irma, will likely receive another direct hit from Maria. After that the model consensus is gradually converging on a recurve scenario, keeping Maria offshore from the US east coast. This is however highly dependent on what happens with the remnants of Hurricane Jose and also on the timing of a trough approaching through the continental US. While a recurve out to sea now appears to be the most likely result, one cannot yet rule out a US impact, particularly from the Carolinas northward. Hopefully we will have confidence in this forecast within the next couple of days.
I will update this diary when the 11 am advisory comes out and during the day as new information comes in. My thoughts are with the people of Dominica and of the US Virgin Islands and Puerto Rico.