Weather alerts have been issued on Friday by the US National Service for Hawaii after two tropical cyclones were passing south of the archipelago back-to-back over the next few days.

The NWS issued a Tropical Storm Warning on Thursday evening, downgraded from a Hurricane Warning posted four hours earlier, Xinhua news agency reported.

Late on Thursday, Tropical Storm Erick was located about 265 miles south of the Big Island and had sustained winds near 70 mph with higher gusts. It was moving west-northwest near 13 mph.

According to National Weather Service meteorologist Melissa Dye, tropical Storm Flossie also on a westward itinerary will enter the east Hawaiian waters on Sunday.

A flash flood watch was issued for the Big Island from Thursday to Saturday. A high surf warning is also in effect for east-facing shores of the island, some of which could see waves up to 20 feet high, making “entering the water very hazardous”, the NWS further said.

Parts of Maui island and Big Island could encounter up to 48 kph of winds and 72 kph of gusts.

According to the NWS, tropical cyclone activity in the eastern part of the North Pacific Ocean has been below average so far in 2019.

(With IANS inputs)