- Storm conditions are expected in parts of the Bahamas Friday.
- Isaiah issued hurricane warnings in parts of Florida.
- The first effects can be felt in parts of Florida once Saturday.
- The forecast for this system is still uncertain due to many factors.
- The latter could affect the massive swath of the East Coast as far north as New England early next week.
Hurricane Isaias (ees-ah-EE-ahs) is expected to strengthen while tracking the Bahamas on Saturday and then moving closer to Florida this weekend, before monitoring the East Coast as far north as New England next week.
A hurricane warning was issued for a portion of Florida’s East Coast, from Boca Raton to the Volusia / Brevard County Line. Storm conditions are expected late Saturday or Sunday.
A hurricane watch has been expanded, 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 storm watch is usually released 48 hours before the expected first appearance of tropical-storm-force winds, conditions that make it difficult or dangerous outside of preparations.
(MORE: Hurricane Season Rules You Need to Know)
Typhoon warnings continue in the Bahamas, including Nassau, Freeport and the Abacos Islands, where storm conditions are expected on Saturday.
Strong winds and rainstorms fell in the southeastern Bahamas, as well as the Turks and Caicos. Wanted winds of over 50 mph were measured in the Turks and Caicos late Thursday night and early Friday. Conditions worsened in the central and northern Bahamas.
Heavy rain triggered severe flooding in many parts of Puerto Rico. Just under 4.5 inches of rain was measured in San Juan on Thursday. Several fallen trees, mudslides and flooding were reported in southwestern Puerto Rico, according to local emergency management. River flooding were recorded by USGS gauges at several locations in Puerto Rico.
(NEWS: Isaiah Dies Leaving Wide Damage in Across Dominican Republic, Puerto Rico)
Below is a look at what we know about the forecast for any potential US and Caribbean impact.
Florida, East Coast Concerns of the US
The expected NHC path below shows that this system is located near Florida’s East Coast this weekend. Isaiah will gradually move to the northeast near the East Coast. This is a mild westward shift compared to previous forecasts.
There are still many reasons for uncertainty in both track and intensity.
It is still early to determine the future track and intensity, about the mainland US and, therefore, the potential impacts including rain, wind, and flooding.
Here is what we actively know today:
The storm is expected to battle relatively undesirable upper winds – doing what meteorologists refer to as shear winds – along its track from the Bahamas and beyond. It is basically a nemesis of tropical cyclones.
However, lukewarm water is plentiful near the Bahamas and off the coast of the Southeast US, a factor that would favor slow growth.
The sums of these two competing factors should rely on slow strengthening as shown in the National Hurricane Center forecast.
Further north, ground contact with Florida could weaken Isaiah on Sunday.
The forward track relies heavily on environmental steering features – the Bermuda high and an upper level that sinks into the air flow over the Mississippi Valley. How strong Isaiah is early next week also plays a role in its track.
There is also great uncertainty about how fast Isaiah is moving near the East Coast. Some computer model forecasts are faster, some are relatively slow. So, the timing of all this can also change.
Isaiah is expected to make it north, then northeast around this week early next week. But exactly when and how sharp the turn that occurs will have a heavy influence on impacts in Florida and along the East Coast. And it depends on the exact orientation and strength of the steering features.
The National Weather Service will release additional weather balloons to assist them with atmospheric contraction agents in the coming days. Hurricane Hunters also sampled the environment around and north of Isaiah tonight to help improve the forecast.
For now, a forecast, near the Florida coast to the east is expected, but may move east or west.
Isaiah is expected to arrive near South Florida early Sunday as a hurricane, and possibly central or northeast in Florida Sunday afternoon. That will result in at least some rain, wind, high surfing, and coastal flooding or hurricane attacks in Florida over the weekend.
A dangerous typhoon is also possible in a storm surge on the Florida Coast.
Here is the current forecast from the National Hurricane Center:
- Jupiter Inlet to Ponte Vedra Beach FL: 2-4 p
- North Miami Beach to Jupiter Inlet FL: 1-3 ft
From there it can pass near the Carolinas Monday, then sweep quickly near parts of the Northeast Seaboard as far north as New England Tuesday or Wednesday.
The spells created by Isaiah could start arriving off the US southeastern coast as soon as Saturday, leading to high surfing and the risk of rip currs. The Surf will remain elevated over time until Isaiah passes.
Further north, here an early look at the weather of tropical-force-force winds is possible.
East Coast residents from Florida to Maine should monitor the progress of this system and prepare their plans go, in case they need to.
Forecast in the Caribbean, Bahamas
As mentioned earlier, Isaiah makes strong wind gusts and heavy rain bands in the northern and central Bahamas.
Rainfall of 4 to 8 inches is most likely in parts of the Bahamas with up to 2 inches in parts of Cuba. Flash floods and mudslides are possible.
Two to four inches of rain is possible from south Florida to east-central Florida Friday night through Monday, with an isolated maximum total of 6 inches, according to the National Hurricane Center.
Heavy rains could also spread to the eastern Carolinas early next week.
Conditions will gradually improve in the Central and Southern Bahamas and the Turks and Caicos until Friday as Isaiah moves north.
A hurricane-force hurricane up to 3 to 5 feet, above ground level, is estimated from the National Hurricane Center, in areas where winds will blow in the Bahamas.
Live surf and rip currents are also expected in Florida this weekend.
Come back to us at weather.com for important updates on Isaiah.
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