- Hurricane conditions are expected in the Bahamas on Friday.
- Isaias has caused hurricane warnings in parts of Florida.
- The first impacts could be felt in parts of Florida as early as Saturday.
- The forecast for this system is still uncertain due to numerous factors.
- Isaias could eventually impact a significant East Coast rush to the north, in New England early next week.
Isaiah hurricane (ees-ah-EE-ahs)) is expected to strengthen as it traverses the Bahamas on Saturday and then moves near Florida this weekend, before tracing the East Coast as far north as New England next week.
A hurricane warning has been issued for part of the East Florida Coast, from Boca Raton to Volusia / Brevard County Line. Hurricane conditions are expected late Saturday or Sunday.
A hurricane hour has widened, now in effect for parts of Florida from the north of the Volusia-Brevard County line to the Flagler / Volusia County Line, and for South Florida from Boca Raton to Hallendale County. A hurricane hour is typically released 48 hours before the first predicted tropical-storm winds occur, conditions that make external preparations difficult or dangerous.
(MORE: Storm season conditions you need to know)
Hurricane warnings continue in the Bahamas, including Nassau, Freeport and the Abacos Islands, where hurricane conditions are expected on Saturday.
Strong winds and rain bands are destroying the southeastern Bahamas, as well as the Turks and Kaikos. Windstones above 50 mph were measured in Turk and Caicos on Thursday night and early Friday. Conditions are deteriorating in central and northern Bahamas.
Heavy rains caused severe flooding in some areas of Puerto Rico. Just under 4.5 inches of rainfall was measured in San Juan on Thursday. Many trees fell, landslides and floods were reported in southwest Puerto Rico, according to local emergency management. River flooding was recorded by USGS meters at several locations in Puerto Rico.
(NEWS: Deadly Isaias has left widespread damage beyond the Dominican Republic, Puerto Rico)
Below is a look at what we know about forecasting for any potential impact in the US and Caribbean.
Florida, the troubled east coast of the US
The NHC route provided below indicates that this system may be located near the East Coast of Florida this weekend. Isaias will gradually move north-east near the East Coast. This is a subtle shift to the west compared to previous predictions.
There are still a number of reasons for this uncertainty, both in the right way and in the intensity.
It is still too early to determine exactly the future trajectory and intensity of this system, in relation to U.S. territory and, therefore, potential impacts including rain, wind, and storm floods.
Here is what we are actively discovering now:
The hurricane is projected to battle somewhat adverse high-level winds – producing what meteorologists refer to as wind shear – along its tracks from the Bahamas and beyond. This is usually a nemesis of tropical cyclones.
However, warm water is plentiful near the Bahamas and the southeastern coast of the US, a factor that would favor slower intensification.
These sums of these two competing factors must be relied upon towards the slow intensification as shown in the forecast of the National Hurricane Center.
Further north, land interaction with Florida could weaken Isaiah on Sunday.
Follow the Considerations
The forecast track will rely heavily on atmospheric steering features – High Bermuda and a high level of wind current in the wind flow over the Mississippi Valley. How strong Isaias is early next week also plays a role in her path.
There is also great uncertainty as to how fast Isaiah moves near the East Coast. Some computer model predictions are faster, some slower. So the timing of all this can change as well.
Isaias is expected to make a northerly, then return the northwest this weekend early next week. But exactly when and how sharp does that big impact happen in Florida and along the East Coast. And it depends on the exact orientation and strength of those leadership traits.
The National Weather Service will release additional weather balloons to help locate these leading atmospheric agents in the coming days. Hurricane hunters are also testing the environment around and north of Isaiah this evening to help improve forecasting.
For now, a forecast, near the east coast of Florida is expected, but may shift east or west.
Isaias is expected to arrive near South Florida very early Sunday as a hurricane, and possibly central or northeastern Florida on Sunday afternoon. This will result in at least some rain, wind, high surf, and coastal flooding or major impact impacts in Florida this weekend.
A dangerous storm surge is also possible along the East Coast of Florida.
Here is the current forecast from the National Hurricane Center:
- Jupiter Inlet in Ponte Vedra Beach FL: 2-4 ft
- North Miami Beach at Jupiter Inlet FL: 1-3 ft
From there it could pass near Carolinas on Monday, then clear quickly near parts of the Northeast Coast as far north as New England on Tuesday or Wednesday.
The swelling created by Isaias could start arriving along the southeastern U.S. coast as early as Saturday, leading to high browsing and the risk of rupture currents. The surf will remain elevated for the duration until Isaias passes.
Further north, here is an early look at when tropical-force winds are possible.
Residents along the East Coast from Florida to Maine should closely monitor the progress of this system and have their plans ready to go, if necessary.
Caribbean, The Bahamas Forecast
As mentioned earlier, Isaiah is producing strong wind gusts and heavy rain bands in northern and central Bahamas.
Rainfall of 4 to 8 inches is likely in parts of the Bahamas with up to 2 inches in parts of Cuba. Floods and clutter are life threatening.
Two to four inches of rainfall is possible from South Florida to east-central Florida on Friday evening through Monday, with isolated maximum amounts of 6 inches, according to the National Hurricane Center.
Heavy rains could also spread to eastern Carolinas early next week.
Conditions will gradually improve in the Central and Southern Bahamas and the Turks and Caicos by Friday as Isaias moves north.
A dangerous storm rise of up to 3 to 5 meters, above ground level, is predicted by the National Hurricane Center, in areas where winds will blow into the sea in the Bahamas.
Life-threatening currents and ruptured currents are also expected in Florida this weekend.
Check back with us at Weather.com for important updates on Isaias.
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