Miami, Florida (CNN) -- Once it clears the Yucatan Peninsula, Tropical Storm Karl could emerge in the Bay of Campeche and became a hurricane by Friday, the National Hurricane Center said Wednesday evening.
Tracking models show Karl crossing the peninsula, picking up strength and heading for the Mexican mainland, possibly reaching it late Friday, forecasters said.
At 8 p.m. ET, Karl had maximum sustained winds of 40 mph (65kph) and it was traveling west-northwest at 15 mph (24 kph).
The storm was 50 miles (80 km) southeast of Campeche, Mexico. A tropical storm watch was in effect for the west coast of the Yucatan Peninsula. A hurricane watch may be posted for portions of the mainland.
"Karl is expected to produce total rain accumulations of 3 to 5 inches over the Yucatan Peninsula, Belize and northern Guatemala with isolated maximum amounts of 8 inches," the center said.
The Atlantic Ocean, meanwhile, sported a pair of hurricanes -- both far from land. Hurricane Julia showed signs of weakening.
At 5 p.m. ET, Hurricane Igor had top sustained winds of 135 mph (215 kph) and was moving to the west-northwest at 8 mph (13 kph), according to forecasters. The storm's center was about 1,015 miles (1,635 km) southeast of Bermuda and 505 miles (815 km) east-northeast of the northern Leeward Islands.
Hurricane-force winds extended up to 45 miles (75 km) from Category 4 Igor's center, and tropical storm-force winds could be felt up to 240 miles (390 km) outward, according to the center.
While the storm is expected to stay north of the Caribbean islands, the islands are expected to experience dangerous surf conditions, along with some wind and rain because of Igor's size, forecasters said.
Meanwhile, in the far eastern Atlantic, Julia was downgraded to a Category 3 storm on Wednesday.
As of 5 p.m. ET, Julia's maximum sustained winds had increased to 125 mph (205 kph), and it was moving northwest at 17 mph (28 kph). The storm's center was about 665 miles (1070 km) west of the Cape Verde Islands.
Julia is expected to maintain its intensity before slowly weakening on Thursday. It is not expected to threaten land.