Hurricane IRMA’s Latest Status, Timing
The center of Irma is located just under 300 miles east of the Leeward Islands and is moving westward
at about 15 mph.
Irma’s maximum sustained winds have increased to 175 mph based on data from NOAA and Air Force
Hurricane Hunter aircraft. Based on wind speed, Irma is the strongest Atlantic hurricane since Felix
and Dean in 2007 which also had maximum sustained winds of 175 mph.
Additionally, Irma is just the 17th Atlantic hurricane to have maximum sustained winds of 175 mph or greater,
according to Dr. Phil Klotzbach, a tropical scientist at Colorado State University.
Hurricane warnings have been issued for the northern Leeward Islands, Puerto Rico and the Virgin Islands.
This includes Antigua, Barbuda, Anguilla, Montserrat, St. Kitts, Nevis, Saba, St. Eustatius, Sint Maarten, St.
Martin, St. Barthelemy, Vieques and Culebra.
Additionally, both a hurricane watch and a tropical storm warning have been issued for Guadeloupe, and a
tropical storm warning is in effect for Dominica.
A hurricane watch is also now in effect for the north coast of the Dominican Republic, from Cabo Engano
to the Haiti border.
Low wind shear, increased mid-level moisture and ample oceanic-heat content favor that Irma will remain
a powerful hurricane (Category 3 or stronger) for the next several days, though some intensity fluctuations
are likely at times.
For the next five days, Irma will move west-northwest on the south side of a ridge of high pressure called the
Bermuda high, centered in the central Atlantic.
By this weekend, Irma will begin to turn north in the direction of a departing southward dip in the jet stream
that will set up in the eastern United States. Where that northward turn occurs will be critical for what impacts
Irma may bring to parts of the southeastern United States.
Here’s a general overview of the timing for impacts from Irma into this weekend.
Potential Impact Timing of Hurricane IRMA
- Leeward Islands: Late Today-Wednesday; tropical storm-force winds will arrive later today.
- Puerto Rico/Virgin Islands: Wednesday- early Thursday
- Dominican Republic/Haiti: Thursday- early Friday
- Turks and Caicos: Late Thursday-Friday
- Bahamas: Friday-this weekend
- Cuba: Friday-this weekend
- Southeast United States: This weekend into early next week, beginning in south Florida Saturday
U.S. Forecast: Watching Florida, Southeast Closely
While it is still too soon to narrow down specifics on the exact path of Irma’s center and eyewall, there
is an increasing chance of a major hurricane strike on at least part of South Florida, including the Florida
Keys, this weekend.
As mentioned before, the vast majority of the forecast guidance indicates Irma will begin to turn more to
the north sometime this weekend.
The strength and expansiveness of the Bermuda-Azores high over the Atlantic Ocean and the timing,
depth and location of a southward dip in the jet stream near the eastern U.S. will dictate where and when
that northward turn occurs.
According to the latest NHC forecast, the center of Irma may be very close to South Florida by Saturday night,
with conditions going downhill already during the day, Saturday.
However, as the NHC reminds us, average errors in the track of the center of an Atlantic tropical cyclone 4 to 5
days out are between 175 and 225 miles, which can make a large difference in impacts.
For now, all residents along the Southeast coast and eastern Gulf Coast, including Florida, Georgia and the Carolinas,
should monitor the progress of Irma closely.
In addition, Irma’s wind field will be large, therefore, dangerous surf and coastal flooding will likely exist throughout
the southeastern U.S. coastline even well away from Irma’s center by late week.