- A wide area of low pressure is likely to become Tropical Storm Isaias in the eastern Caribbean.
- Tropical Storm Warnings and Alerts Released from Leeward Islands to Southeast Bahamas
- Heavy rains are expected until Thursday from the Leeward Islands to Puerto Rico and Hispaniola.
- Rain could cause flash floods and landslides.
- The prognosis for this system beyond the Caribbean is highly uncertain due to multiple factors.
- The first impacts could be felt in parts of Florida as early as this weekend, but it’s too early to know the details.
Tropical storm warnings have been issued for parts of the Caribbean, including Puerto Rico, as a disturbance expected to become Tropical Storm Isaias could hit Florida this weekend.
The National Hurricane Center (NHC) named this system “Possible Tropical Cyclone Nine” on Tuesday, a procedure that allows NHC to issue warnings, alerts, and warnings for a system that has not yet been developed but poses a threat of force. of tropical storm or hurricane force winds on land in 48 hours.
(PLUS: Hurricane season terms you need to know)
The latest clocks and warnings are shown on the map below, from the Leeward Islands to southeast Bahamas. A warning means tropical storm conditions are expected in the next 36 hours. A watch means that tropical storm conditions are possible within 48 hours.
Current watches 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.)
While this large system is slowly consolidating its thunderstorms, it has not yet developed a well-defined low-pressure closed center.
Once you develop enough thunderstorms near a closed low pressure center, this system will be designated as Tropical Storm Isaias (ees-ah-EE-ahs)
Below is a look at what we know about the forecast for any potential impacts from the US and the Caribbean.
Florida, southeastern United States?
The NHC projected path below shows that this system could be located near or on both sides of the Florida peninsula this weekend. However, this forecast is not as straightforward as it might seem.
Current information and forecast 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 a number of reasons for this uncertainty, which is quite common for tropical cyclones heading to the Caribbean Sea.
First, this system is in a formative state, with no clear surface low pressure center.
Finally, a group of thunderstorms should begin to take over this major disturbance. Where that occurs is uncertain, and could cause a significant change in position and therefore in the forecast path of this system.
In addition to the uncertain track forecast, this system has multiple obstacles to fight in the coming days.
One of these obstacles is the expected trajectory of this system on the mountainous terrain of Hispaniola (Dominican Republic and Haiti). That terrestrial interaction could disrupt the system, at least for a time.
This system may also have to combat unfavorable upper-level winds, producing what meteorologists call wind shear, and / or dry air along its Caribbean and Bahamas route. Both are nemesis from 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).
The bottom line is that it is too early to accurately determine the future trajectory and intensity of this system, especially with respect to the continental United States.
If this system threatened the continental United States, it could do so first on the Florida Peninsula as early as this weekend.
However, possible outcomes for the continental United States range from a route east of the Gulf of Mexico to a route over at least parts of the US east coast.
Residents along the Southeast and Gulf coasts must closely monitor the progress of this system and have their plans ready go, if necessary.
Caribbean Forecast
This system is tracking the Leeward Islands with heavy rains and gusty winds at this time.
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 should then spread rain and gusty winds to Puerto Rico and the Virgin Islands beginning Wednesday afternoon and passing near or over Hispaniola on Thursday.
While some rain is needed to help long-term drought In eastern and southern Puerto Rico and the Virgin Islands, locally strong bands of rain can cause dangerous flash floods and landslides, particularly on higher ground.
The NHC says that total rainfall of up to 10 inches is possible on these islands.
The mountainous terrain of Hispaniola will also make it very prone to flooding and landslides. Locally, up to 8 inches could drop in some areas through Thursday.
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.)
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