Good morning from the forecast cone.
Hurricane Irma remains a powerful category 5 hurricane with sustained winds of 185 mph. Irma made landfall last night on the island of Barbuda, which suffered the full force of the storm and spent about an hour inside the eye. News out of Barbuda is hard to find this morning. Hopefully we’ll know more later today.
Anguilla is experiencing the eyewall now and should emerge in the eye shortly. The British Virgin Islands are in or near the direct path and Puerto Rico, while slightly south of the forecast path, will be experiencing severe conditions, especially on the north coast but also inland flooding and local wind damage where straight line winds get channeled or where there may be embedded tornadoes. Irma is now a large storm so most of Puerto Rico, even the south side, is likely to see hurricane force winds.
Hurricane warnings are now up for the north coast of Hispaniola as well as the southern Bahamas and the Turks and Caicos. A number of those islands are likely to also get a direct impact of the storm core.
The longer term forecast is not encouraging for those of us in South Florida. While the operational runs of both the European ECMWF model and the American GFS model have flip-flopped some, the ensembles of both are gradually converging in the vicinity of the Florida peninsula.
Here are last nights ECMWF ensembles:
and here are the GFS ensembles for the same timeframe:
Both the operational ECMWF and the operational GFS make the right turn just barely east of Florida, passing between Bimini and Miami before going north to a South Carolina landfall, but the uncertainty regarding the timing of that turn is still fairly high, so the scenario of the previous few ECMWF runs which struck SW Florida is well within the range of possibility, as is even a slightly earlier turn.
The 6Z operational GFS, which is just completing, is essentially identical to the 0Z run.
I will update this diary as I can if we get new reconnaissance data of note, and after the mid-day model runs.
Wednesday, Sep 6, 2017 · 2:53:55 PM +00:00 · jrooth
Finished my South Miami prep so have some time online.
I just did a little verification of the last GFS forecasts vs reality and Irma is noticeably south of the forecast even at 6 hours and looks likely to be 30 miles south at 12 hours. Not sure if that will make a huge difference down the road but it doesn’t inspire confidence.
Wednesday, Sep 6, 2017 · 2:59:43 PM +00:00 · jrooth
11 AM advisory: Irma is still a 185 mph category 5. (BTW this is really exceptional for a storm to maintain cat 5 this long, let alone such a high level of cat 5.)
Forecast track has shifted a little more east, but still impacting South Florida: