Hurricane Irma continues to strengthen and is now the strongest Atlantic storm in a decade. The extraordinarily powerful, well-organized storm is currently heading toward Puerto Rico and could be in Florida by the weekend.
A Hurricane Warning is in effect for...
- Antigua, Barbuda, Anguilla, Montserrat, St. Kitts, and Nevis
- Saba, St. Eustatius, and Sint Maarten
- Saint Martin and Saint Barthelemy
- British Virgin Islands
- U.S. Virgin Islands
- Puerto Rico, Vieques, and Culebra
Irma is currently carrying sustained winds of 180 mph. That’s far over the 157 mph minimum for a Category 5 storm. Winds at this level are likely to be devastating even for well-built structures generally regarded to be constructed to survive strong hurricanes. Irma has maintained an extremely distinct eye-wall and organization, clear signs of a storm that has unusual intensity and potential. Central pressure is currently around 931 mb.
Storm surge as Irma reaches the US Virgin Islands is expected to be up to 11 feet. Currently Irma is moving more rapidly than Hurricane Harvey and should not linger for long periods in the same area. However it is still expected to deliver up to 18 inches of rain as it passes over the Caribbean, adding flash floods and mud slides to other destruction.
Earlier models had indicated a good possibility that Irma would skirt the US coast as a weak high-pressure system in the North Atlantic allowed it to curl off to the northeast. However, that path seems increasingly less likely as the storm seems likely to strike somewhere in Florida.
Puerto Rico, currently laboring under financial issues and tight restrictions on government spending, is facing a storm of amazing ferocity. Irma has grown until hurricane-force winds extend 60 miles from the center of the storm, and with peak winds spiking well over 180mph. It is expected to retain this strength over the next day as it moves toward Puerto Rico. Even if Florida should somehow end up dodging Irma, it’s almost inevitable that millions of Americans in Puerto Rico and the US Virgin Islands are about to be receiving end of a devastating storm.
This image of the areas of tropical storm and hurricane wind strength gives a sense of the growth of the storm over the last day and its increasing size as it moves toward Puerto Rico.
At 180 mph, the center of the storm may be nothing less than a giant “eraser,” scrubbing the area of even those buildings that meet stringent building guidelines. Florida’s “high velocity hurricane zone” plans for winds up to 150 mph in the areas around Miami. Coastal areas further north follow guidelines designed to guard against 120 mph winds.
All of those standards could come in for a test from Irma. Though there is still a possibility that Irma could either turn to the right and avoid making a direct landfall, or pass over a large island, such as Cuba, and diminish in strength.
The most accepted models now have the storm brushing along the US coast near Miami at Category 5, then hooking back out to sea, losing strength, and swinging back into the US coast as a weaker Category 2-3 storm, probably on the Georgia coast. But with the storm still picking its way across islands and the possibility that the North Atlantic high could alter either way, such a precise description of the path is unlikely to be correct in every detail.
However, anyone in south Florida, or on the Atlantic cost of either Florida or Georgia should prepare for the storm now. Do not assume it will miss. Do not assume it will weaken. And particularly if you are in south Florida, do not assume that any structure is built to a level to survive a direct impact.
It’s worth noting that Tropical Storm Jose is following a similar path to Irma and will likely grow to hurricane strength by Thursday. However, it seems likely that Jose will then swing to the north.