Tropical Storm Erika threatens Leeward Islands

Tropical Storm Erika formed on Monday night and will track toward the Leeward Islands through the middle of the week.

As Tropical Rainstorm Danny tracks across the northern Caribbean islands, Erika will take a track slightly farther north and will bring another round of rainfall.

This system will be steered westward by a large dome of high pressure across the Atlantic during much of this week.

“This high is expected to guide Erika on a west-northwest course through Thursday,” said AccuWeather Hurricane Expert.

Erika is currently located well east of the Leeward Islands but will be getting closer over the next two days.

“Erika will be moving through an environment with warm waters and generally low wind shear,” AccuWeather Meteorologist said.

Tropical systems are most likely to strengthen in areas of weak wind shear. If wind shear is too strong, the system becomes disorganized and weakens.

“Wind shear is when strong winds near the surface and aloft blow strongly from different directions,” AccuWeather Senior Meteorologist said.

Danny thrived late last week in a zone of low wind shear. Once it moved into an area of increasing wind shear near the Leeward Islands, the system weakened rapidly.

The future of Erika and the track it takes will depend on how much it can get its act together in the short term.

“If Erika does not slowly strengthen and instead weakens, more than likely Erika will take a path more westward similar to Danny where it will run into more shear,” said meteorologist. A path like Danny would also take it over more land where it will weaken faster.

A track into the northern islands of the Caribbean would bring another dose of needed rainfall.

Much of the eastern half of Puerto Rico is under at least a severe drought, according to the United States Drought Monitor. Because of this, water rationing programs are in effect on the eastern side of the island.

If this system slices north of the Leeward Islands, where there will be less land interaction, then it could survive and perhaps strengthen again. In this scenario, steering winds north of the Caribbean Islands will likely allow the system to track northwestward and then northward over the western part of the Atlantic basin near the Southeast United States coast.

Erika is predicted to move across the northern Caribbean as a strong tropical storm, but it could be as strong as a minimal Category 1 hurricane this weekend.

The exact path this weekend into next week is uncertain at this time.

“All interests in the northeast Caribbean, Bahamas, Florida and the Southeast United States should closely monitor the progression of this system,” meteorologist said.

The AccuWeather Hurricane Center will continue to provide information on Erika, as well as all other tropical features across all ocean basins.

Despite a quiet first half of the hurricane season across the Atlantic, late August through September are typically the peak of tropical activity.

At this point in the hurricane season, water temperatures are at their warmest. This gives disturbances moving across the Atlantic from Africa the best chance for development.

“We are also watching a tropical wave near the Cape Verde Islands but further development seems unlikely at this time,” said meteorologist.

In May, AccuWeather predicted eight tropical storms, four of those to become hurricanes across the Atlantic Basin during 2015. Erika is the fifth tropical storm of the season with Danny being the only storm becoming a hurricane.