Dangerous Hurricane Irma was intensifying as it approached the northern Lesser Antilles Islands on Monday morning, and island residents in the path of Irma need to rush preparations to completion as the storm heads west-southwest at 14 mph. A NOAA hurricane hunter aircraft in the storm found that Irma’s central pressure was steadily dropping Monday morning, reaching 944 mb at 11 am EDT. Irma’s top sustained winds are estimated at 120 mph, and winds may not yet have fully responded to this pressure drop. Update: Based on Hurricane Hunter measurements, NHC raised Irma’s top sustained winds at 5:00 pm EDT to 130 mph, making it a Category 4 storm. Irma is expected to be a major Category 4 hurricane when it passes very close to the northern Lesser Antilles Islands on Tuesday, near Puerto Rico and the Virgin Islands on Wednesday, and the Turks and Caicos Islands and Hispaniola on Thursday. As of 5 pm EDT Monday, Hurricane Warnings are in effect for the northern Leeward Islands, and Hurricane Watches are up for the U.S. and British Virgin Islands and Puerto Rico.
Tropical storm-force winds are expected to begin affecting the east coast of Florida and the Florida Keys on Friday night (Figure 1 below). An evacuation decision for the Florida Keys may have to come as early as Tuesday, since the Keys require 3+ days to evacuate. As of 5 pm EDT, far southeast Florida, including Miami, was in the 5-day cone of uncertainty for Irma.