11:00 AM Update: Max wind now up to 180 mph!
Latest NOAA and US Air Force measurements show that the maximum sustained wind within Hurricane Irma has increased to 175 mph, making the storm an "extremely dangerous" category 5 hurricane! The center of Irma is about 270 miles east of Antigua. The most likely track at this time takes the center of Irma to just south of the Florida Keys by 2:00 A.M. Sunday. It is likely to curve sharply to the north after that, but the models are still debating whether the center will move north across the entire Florida Peninsula from there, move up along the Florida Gulf Coast, or go up Florida's east coast and then into the Carolinas. (Keep in mind the average NHC error forecasting a hurricane's track is 175 miles, 4 days out and 225 miles 5 days out). Regardless, the threat that this hurricane will make landfall in Florida and/or somewhere in the southeastern U.S. continues to increase. Irma is expected to remain a major hurricane for the next few days. Fluctuations in strength can be expected. Current conditions could support a little bit of additional strengthening. Some weakening will occur if the center moves over some of the islands and/or when "eyewall replacement cycles" occur, which is normal in a mature hurricane.
Here is the latest official track forecast from the National Hurricane Center. Note the Hurricane Watches and Warnings that are now in place across parts of the Dominican Republic, Puerto Rico, and the islands.
Many people (who live in areas that can be affected) don't prepare properly in advance for a hurricane. If you know someone in Florida who is wondering whether or not they have all their bases covered, you can foward these links to them regarding hurricane preparation. They are basically boilerplate prep outlines, but can help jog your memory about some things you might not have thought of in advance:
NOAA Hurricane Prep Page
FEMA Hurricane Prep Page
ECMWF Ensemble Plots
ECMWF Operational Run Forecast For 8 AM, Monday, September 11.
GFS Ensemble Plots
GFS Operation Run Forecast For 8 AM, Sunday, Sept 10
HWRF (Tropical Model) Forecast For 8 AM, Sunday, September 10