- Hurricane conditions are expected in parts of the Bahamas on Friday.
- Isaias has triggered hurricane warnings in parts of Florida.
- The first impacts could be felt in parts of Florida as early as Saturday.
- The prognosis for this system is still uncertain due to multiple factors.
- Isaias may ultimately affect a sizable swath of the east coast as far north as New England early next week.
Hurricane Isaias (ees-ah-EE-ahs) is expected to strengthen as it moves through the Bahamas through Saturday and will then move near Florida this weekend, before tracing the east coast to northern New England next week.
A hurricane warning was issued for part of the east coast of Florida, from Boca Raton to the Volusia / Brevard County line. Hurricane conditions are expected on Saturday afternoon or Sunday.
Hurricane watch has been expanded, now in effect for parts of Florida from the northern Volusia-Brevard County line to the Flagler / Volusia County Line, and to southern Florida from Boca Raton to Hallendale County. A hurricane watch is generally issued 48 hours before the first anticipated occurrence of tropical storm force wind, conditions that make exterior preparations difficult or dangerous.
(PLUS: Hurricane season terms you need to know)
Hurricane warnings continue in the Bahamas, including Nassau, Freeport, and the Abacos Islands, where hurricane conditions are expected through Saturday.
Clocks and warnings
(A warning is issued when tropical storm or hurricane conditions are possible within 48 hours. A warning is issued when such conditions are expected within 36 hours.)
Strong winds and bands of rain blow across the southeastern Bahamas, as well as the Turks and Caicos Islands. Wind gusts of over 50 mph have been measured in the Turks and Caicos Islands on Thursday night and Friday night. Conditions deteriorate in central and northern Bahamas.
Heavy rains caused severe flash floods in various areas of Puerto Rico. Just under 4.5 inches of rain was measured Thursday in San Juan. Multiple fallen trees, landslides and floods were reported in southwest Puerto Rico, according to local emergency management. River floods It has been registered by USGS meters in various places in Puerto Rico.
(NEWS: Deadly Isaias has left widespread damage throughout the Dominican Republic, Puerto Rico)
Below is a look at what we know about the forecast for any potential impacts from the US and the Caribbean.
Florida, East Coast, United States concern
The NHC projected route below shows that this system could be located near the east coast of Florida this weekend. Isaias will then gradually move northeast near the east coast. This is a subtle shift to the west compared to previous forecasts.
Current information and projected route
(The red shaded area indicates the potential path of the center of the system. It is important to note that the impacts (particularly heavy rainfall, high waves, coastal flooding, winds) with any tropical cyclone generally extend beyond its predicted path) .
There are still a number of reasons for this uncertainty both on the track and in intensity.
It is still too early to accurately determine the future trajectory and intensity of this system, relative to the continental United States, and therefore potential impacts including rain, wind, and storm floods.
This is what we are actively discovering right now:
Intensity considerations
The hurricane is forecast to combat somewhat unfavorable upper-level winds, producing what meteorologists call wind shear, throughout its trajectory from the Bahamas and beyond. This is usually an enemy of tropical cyclones.
Current satellite, wind shear analysis
(Cloud areas are shown in white. Areas of strong wind shear, the difference in wind speed and direction with height, are shown in purple. High wind shear is hostile to mature tropical cyclones and those that try to develop).
However, warm water is abundant. near the Bahamas and the southeastern coast of the United States, a factor that would favor slow intensification.
This sum of these two competitive factors should lean toward slow intensification as shown in the National Hurricane Center forecast.
Further north, land interaction with Florida could weaken Isaías on Sunday.
Follow-up considerations
The predicted future path is largely based on directional characteristics in the atmosphere: the height of Bermuda and a drop in wind flow over the Mississippi Valley from the upper level. How strong Isaias is early next week also plays a role in her path.
There are also great uncertainties about how fast Isaias moves near the east coast. Some computer model forecasts are faster, some slightly slower. So the timing of all this can also change.
Isaias is expected to turn north, then northeast, and change this weekend early next week. But exactly when and how abruptly that turn occurs will greatly influence the impacts in Florida and along the east coast. And that depends on the exact orientation and strength of those steering characteristics.
The National Weather Service will launch additional weather balloons to help discover these atmospheric direction agents in the coming days. Hurricane hunters are also sampling the environment around and north of Isaías tonight to help improve the forecast.
Direction factors at play
(Bermuda’s elevation and an upper-level channel over the Mississippi Valley may help guide the system in the southeastern US, assuming it survives until then. The National Hurricane Center’s potential forecast path is shown in red).
For now, a forecast is expected, near the east coast of Florida, but it could move east or west.
Isaias is expected to arrive near South Florida very early on Sunday as a hurricane, and possibly Sunday afternoon in central or northeast Florida. That would trigger at least some rain, wind, high waves, and coastal flooding or storms in Florida this weekend.
Possibility of winds with tropical storm force and more probable arrival times
(The contours above show the possibility of tropical storm force winds (at least 39 mph), according to the latest forecast from the National Hurricane Center.)
A dangerous storm is also possible along the east coast of Florida.
Here’s the current forecast from the National Hurricane Center:
- Jupiter entrance to Ponte Vedra Beach FL: 2-4 feet
- North Miami Beach to Jupiter Inlet FL: 1-3 ft.
From there it could pass near the Carolinas on Monday, then quickly sweep near parts of the northeast coast to northern New England on Tuesday or Wednesday.
The waves generated by Isaias could start arriving along the southeastern coast of the US as early as Saturday morning, causing high waves and the danger of rip currents. The surf will remain high all the time until Isaias passes.
Further north, here is an early look when tropical storm force winds are possible.
Residents along the east coast from Florida to Maine must closely monitor the progress of this system and have their plans ready. go, if necessary.
Caribbean, Bahamas Forecast
As mentioned above, Isaias is producing strong gusts of wind and bands of heavy rain in northern and central Bahamas.
Current wind field
(The orange circle shows the extent of tropical storm force winds in the system (at least 39 mph). The purple circle indicates the extent of hurricane-force winds (at least 74 mph), according to the National Hurricane Center .
It is likely to rain 4 to 8 inches in parts of the Bahamas with up to 2 inches in parts of Cuba. Flash floods and life-threatening landslides are possible.
Two to four inches of rain is possible from south Florida to central-east Florida Friday through Monday night, with a maximum isolated total of 6 inches, according to the National Hurricane Center.
Heavy rains may also spread to eastern Carolinas early next week.
Rain forecast
(This should be interpreted as a broad perspective of where the heaviest rain can fall and can change depending on the predicted path of the tropical cyclone. Higher amounts can occur when the rain bands stagnate over a period of a few hours.)
Conditions will gradually improve in central and southern Bahamas and the Turks and Caicos Islands through Friday as Isaiah moves north.
A dangerous storm of up to 3 to 5 feet, above ground level, is forecast from the National Hurricane Center, in areas where shore winds will blow in the Bahamas.
Life-threatening rip currents and hangovers are also expected this weekend.
Check back with weather.com for important updates on Isaias.
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