Uh Oh– Tropical Storm Irene reportedly “churned” across the northwestern Caribbean Sea on Sunday, showing every indication of becoming the season’s first hurricane. Irene is expected to reach hurricane strength by Monday as it nears the southern coast of the Dominican Republic and Haiti. If the forecast by the National Hurricane Center holds, it could approach South Florida late Thursday or early Friday as a hurricane. Get full details after the jump!!

@ItsLukieBaby

(Miami Herald)–Eric Blake, a hurricane specialist at the center in West Miami-Dade County, cautioned that there was still uncertainty in the forecast and the storm was still a long way away – about 1300 miles from Miami at 8 a.m. Sunday. Most of the center’s computer models also steered the storm toward South Florida but the timing of a turn could take it south of the peninsula or offshore over the Bahamas.

“It is still really early,” said Eric Blake, hurricane specialist at the National Hurricane Center. “It is certainly something that residents of South Florida should monitor.”

The biggest question about Irene was how powerful it might become. Though its winds remained at 50 mph overnight, the system appeared to becoming more compact and better organized. Forecasters said it was also entering an area with atmospheric conditions and warm waters that would fuel further strengthening. The only real hurdles in its way were the mountains of Hispaniola and Cuba.

How well it survives a crossing will play a key role in its development once it enters the Florida Straits. The official forecast holds Irene to a Category 1 hurricane as it approached South Florida but forecasters stress that its difficult to estimate intensity with a storm four or five days off.

The Dominican Republic posted a hurricane warning Sunday for the southern coast and tropical storm watch for the northern coast. A tropical storm watch was up for Haiti. Both countries, drenched by Tropical Storm Emily only weeks ago, could be facing severe flooding and potentially deadly mudslides again. Forecasters predicted from six to 10 inches of rainfall across Hispaniola beginning Monday – with 20 inches possible in some areas.

Puerto Rico also posted a hurricane warning and the U.S.Virgin Islands and many of the islands of the Northwestern Caribbean were all under tropical storm warnings. From four to seven inches of rain, with up to 10 inches in isolated spots, was forecast.

The National Hurricane Center also reported that Tropical Storm Harvey made landfall over Belize on Saturday and was weakening as it headed to northern Guatemala.

The storm is expected to bring as much as 6 inches of rain to parts of Honduras, Guatemala, Belize and Mexico’s Yucatan Peninsula. Forecasters say flash floods and mudslides are possible.