Update: 11 p.m.

Tropical Storm Walaka was about 725 miles south-southwest of Honolulu tonight, moving toward the west near 16 mph.

Maximum sustained winds are near 40 mph with higher gusts, which keeps Walaka at a tropical storm. It’s expected to intensify steadily through Sunday and become a hurricane by Sunday night.

Rapid intensification is then forecast Sunday night through Tuesday, weather officials said.

Tropical-storm-force winds extend outward up to 50 miles from the center.

6 p.m.

Tropical Storm Walaka continues to move westward near 15 mph far south of the isles.

At 5 p.m., Walaka was located about 705 miles south-southwest of Honolulu.

It’s expected to turn toward the northwest Sunday night and Monday.

Maximum sustained winds are near 40 mph, and steady strengthening is expected for the next two to three days.

Tropical-storm-force winds extend outward up to 60 miles from the center.

11:05 a.m.

Tropical Storm Walaka has formed south of Hawaii and was expected to strengthen over the next two or three days, according to the Central Pacific Hurricane Center.

As of 11:05 a.m., Walaka was located about 680 miles south of Honolulu and about 785 miles east-southeast of Johnston Island. Walaka was packing maximum sustained winds of 40 mph with higher gusts.

Walaka was moving west near 15 mph. Forecasters said the motion was expected to continue today through tomorrow with a turn toward the northwest Sunday night through Monday. Forecasters are predicting Walaka will turn toward the north early Tuesday.

“Walaka is forecast to become a hurricane by Sunday, and along the forecast track, hurricane conditions could be experienced on Johnston Island as early as Monday night,” the forecast said.

Walaka is expected to weaken beyond Tuesday.

Tropical-storm-force winds extend outward up to 45 miles from the eye.

7:27 a.m.

The Central Pacific Hurricane Center today said a tropical cyclone is likely to form in the next 48 hours just south of Honolulu.

“Showers and thunderstorms associated with an area of low pressure” are located about 650 miles south of Honolulu and continues to become better organized early this morning, according to the forecast.

It will likely develop into a tropical depression later today or tonight while it moves westward about 15 mph to the south of Hawaii, the forecast said.

No tropical cyclones are expected elsewhere in the next five days, forecasters said.