ABC NewsBy IVAN PEREIRA, ABC News

(NEW YORK) — The storm has already caused catastrophic flash flooding and mudslides in Puerto Rico.

Hurricane Isaias, which strengthened into a Category 1 storm overnight, will hit the Bahamas Friday with torrential rains and high winds before taking aim at eastern Florida, according to forecasters.

The National Hurricane Center said in its 11 a.m. update that the islands will experience wind gusts up to 75 miles per hour and heavy squalls throughout the day. Four to eight inches of rain is expected to fall in the Bahamas, according to the NHC.

“These rainfall amounts will lead to life-threatening flash flooding and mudslides, as well as river flooding,” the NHC said in an earlier report.

Forecasters predict the storm will travel northwest and arrive in southeast Florida on Saturday and Sunday. The east coast of Florida is under hurricane watch from Deerfield Beach to the Volusia-Brevard County line, according to the NHC.

Parts of the state could see two to four inches of rain with isolated maximum totals of six inches, according to the current forecast.

“These rainfall amounts could result in isolated flash and urban flooding, especially in low-lying and poorly drained areas,” the NHC said.

The NHC added that its current models show Isaias strengthening, but the forecast of a possible Category 2 storm was removed. The NHC forecast cone has shifted slightly west, indicating the storm could affect parts of the Carolinas Sunday night into Monday.

The latest forecast track also accounts for some type of transition into a post-tropical or extra-tropical low as it travels up the East Coast.

Florida officials are on high alert and watching the storm closely. Gov. Ron DeSantis announced Friday that he has declared a state of emergency in every coastal county on the east side of the state from Miami-Dade to Nassau Counties.

The governor said the state is preparing to create shelters and will activate them depending on the storm’s path. COVID-19 testing sites that are in those counties would be closed, but the governor noted that the ones located on the west side of the state will remain open.

NASA and SpaceX said Friday they decided to move forward with plans to bring astronauts Robert Behnken and Douglas Hurley home to Earth with a splashdown on Sunday.

Officials in Miami-Dade County announced Thursday that parks and beaches would close in anticipation of the storm.

Isaias already caused tremendous damage to Puerto Rico and the Dominican Republic. Mudslides left people and cars stranded in the streets and the storm knocked out power to 400,000 customers across Puerto Rico, according to authorities.

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