- Tropical Storm Laura is moving into the Leeward Islands.
- Tropical storm warnings have been issued from the Leeward Islands to Haiti.
- Rainfall flooding is the primary concern in these areas this weekend.
- Laura may approach parts of Florida and the Gulf of Mexico next week.
- The intensity and track for this system is highly uncertain when it approaches the U.S.
- It’s too early to determine what, if any, impacts the U.S. mainland may see.
Tropical Storm Laura will sweep into Puerto Rico, the Virgin Islands and Hispaniola bringing locally heavy rain and gusty winds this weekend. Laura may then head toward parts of Florida and the Gulf of Mexico early next week, possibly as a hurricane. However, its forecast intensity and track are highly uncertain.
This is the earliest the ‘L’ named storm has formed on record. The previous record was Luis on Aug. 29, 1995, according to Phil Klotzbach, tropical scientist at Colorado State University.
Leeward Islands, Puerto Rico Forecast
Tropical Storm Laura is likely to move rather quickly to the west-northwest over the next few days on the southern periphery of a high-pressure system to its north.
Tropical storm warnings have been issued for parts of the northern Leeward Islands, the Virgin Islands, Puerto Rico, the Dominican Republic and Haiti. Tropical storm conditions are expected within the warning area within 24 hours.
Tropical storm watches have been posted for the southeastern Bahamas and the Turks and Caicos Islands. This means tropical storm conditions are possible within the next 48 hours.
Clusters of showers and gusty winds are already spreading through the Lesser Antilles, Virgin Islands and Puerto Rico, and will continue spreading westward into Saturday.
It is the threat of heavy rainfall, which isn’t strictly dependent on Laura’s strength, that could be the primary danger this weekend.
In Puerto Rico, the Virgin Islands, parts of Hispaniola and eastern Cuba, rainfall totals of 3 to 6 inches are possible, with maximum amounts up to 8 inches, according to the National Hurricane Center.
1 to 3 inches of rainfall is expected in the northern Leeward Islands, southeastern Bahamas and the Turks and Caicos, with maximum rainfall totals up to 5 inches.
This rainfall could trigger dangerous flash flooding and mudslides in elevated terrain.
The National Weather Service has issued a flash flood watch for Puerto Rico and the Virgin Islands. The NWS says there is a high risk of flash flooding, and mudslides in steep terrain this weekend.
Last month, what eventually became Isaiah dumped 6 to 12 inches of rain in parts of Puerto Rico, leading to significant flash flooding.
Uncertain Forecast Ahead For the U.S.
The National Hurricane Center forecast shows Laura approaching Florida and the Gulf of Mexico as either a strong tropical storm or hurricane early next week. However, this forecast is not nearly as straightforward as it might seem and you can expect significant changes over the next several days.
Warm ocean water is one factor that favors the steady strengthening of this system through the weekend.
However, Laura’s potential interaction with mountainous terrain in Puerto Rico, Hispaniola and Cuba could disrupt the system. It may also battle dry air and some modest wind shear, both typically nemeses of tropical cyclones.
If that wasn’t complicated enough, there’s the potential that once Laura moves into the Gulf of Mexico, it could interact with future Tropical Storm Marco once that storm is also in the Gulf. Those conflicting forecast factors mean there is a wide range of outcomes that remain possible.
Here are some, but not all, of the scenarios being depicted in various computer model forecast guidance.
1. This system approaches Florida, then moves into the Gulf of Mexico as a tropical storm or hurricane.
2. Dry air and/or land interaction cause this system to dissipate prior to reaching Florida or the Gulf of Mexico.
3. The system remains weak or even dissipates over the next several days, but then reorganizes and strengthens as it approaches Florida or tracks into the Gulf of Mexico.
The bottom line is it’s too early to know what, if any, impacts this system might bring to other parts of the Caribbean or mainland United States. If this system does reach the mainland United States, it would not be until early next week, first in parts of Florida.
All interests along the Gulf Coast and Southeast coast, including Florida, should monitor the forecast closely. Check weather.com for updates.
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