by Danica Coto, From PHYS.ORG

Tropical Storm Gabrielle was downgraded to a depression Thursday as it lashed the U.S. territory of Puerto Rico with heavy rains and swirled toward the Dominican Republic.

The storm was about 30 miles (50 kilometers) south-southwest of Punta Cana, Dominican Republic, in late afternoon and was moving northwest at 9 mph (15 kph) with winds of up to 30 mph (50 kph). It was expected to weaken further in the next two days as it passes over or near the eastern Dominican Republic.

Puerto Rico Gov. Alejandro Garcia Padilla had activated the National Guard, canceled classes at all public schools and closed central government agencies as a precaution.

Heavy rains were still expected across Puerto Rico, state meteorologist Ernesto Morales said.

“We should not lower our guard,” he said. “The storm is very dangerous. There’s a very high possibility of flooding.”

Falling trees brought down a telephone post in the central town of Ciales, while officials said crews were working to clear roads after small landslides in the central mountain town of Utuado and the southeastern town of Yabucoa. Minor flooding was reported in the Caribbean island’s southeast.

Several residents in the northern municipality of Bayamon were relocated because a nearby mountain had already experienced landslides in recent weeks amid persistent wet weather.

The storm was expected to drop up to 8 inches (20 centimeters) of rain in central Puerto Rico, and up to 4 inches (10 centimeters) elsewhere in Puerto Rico as well as in the U.S. Virgin Islands and eastern portions of the Dominican Republic. Officials in the U.S. Virgin Islands closed all schools in St. Croix.

Miguel Rios, director of Puerto Rico’s emergency management agency, said the storm was interacting with a cluster of weather systems hovering above Puerto Rico’s northeastern coast.

“In the next 36 hours, we can experience heavy rains at any moment,” he said. “We must remain on alert.”

Some 14 inches (36 centimeters) drenched the capital of San Juan in July, making it the wettest July ever recorded for Puerto Rico.

For more on this story go to:

http://phys.org/news/2013-09-ts-gabrielle-downgraded-depression-caribbean.html

From Dr Jeff Masters Weather Underground

Forecast for Gabrielle

Wind shear is expected to steadily increase as Gabrielle heads northwest over the next few days. The storm will also be encountering the high mountains of Puerto Rico and Hispaniola, which should act to further disrupt the circulation. The tropical disturbance to the northeast of Gabrielle will also act to pull it apart, and it appears likely that Gabrielle will dissipate by Friday morning, unless the surface center can reform underneath the heaviest thunderstorms 150 miles to the east-northeast of the surface center. Gabrielle or its remnants should begin heading to the north over the weekend, and may pass close to Bermuda next week.

Elsewhere in the Atlantic

A tropical wave over the extreme Southwestern Gulf of Mexico’s Bay of Campeche (Invest 99L) will move ashore on the Mexican coast near Tampico on Friday. Satellite images show that 99L has a moderate area of heavy thunderstorms that are slowly increasing in size and intensity. Wind shear is moderate and water temperatures are a warm 30°C, so 99L will likely show steady development until landfall on Friday. In their 8 am EDT Thursday Tropical Weather Outlook, NHC put the 5-day and 2-day odds of development at 30%. A hurricane hunter aircraft is scheduled to check out the disturbance Thursday afternoon.

A tropical wave in the Eastern Atlantic about 450 miles west-southwest of the Cape Verde Islands (Invest 98L) is headed west-northwest at about 10 mph. Satellite images show that 98L has a decent amount of spin, but a very limited amount of heavy thunderstorms. Wind shear is moderate and water temperatures are a warm 28°C, so 98L may show some slow development today and Friday. By Saturday, 98L will encounter drier and more stable air, and be over waters barely warm enough to support a tropical cyclone–26.5°C. In their 8 am EDT Thursday Tropical Weather Outlook, NHC put the 5-day and 2-day odds of development at 10%.

A strong tropical wave is predicted to emerge from the coast of Africa on Saturday, and the GFS model develops this wave into a tropical depression near the Cape Verde Islands by Monday. The storm is expected to track to the northwest into a region of ocean where very few tropical cyclones ever make the long crossing of the Atlantic Ocean to threaten North America. Both the GFS and European models predict that this system will develop into a hurricane next week. In their 8 am EDT Thursday Tropical Weather Outlook, NHC put the 5-day odds of development at 30%.

Jeff Masters

For more on Weather Underground go to:

http://classic.wunderground.com/tropical/