Remnants of former Tropical Storm Ela are expected to drift over the islands this weekend, touching off heavy humidity and spotty rainfall.
National Weather Service forecasters say the storm’s leftovers will open into a trough that will disrupt tradewinds, while moisture linked to the weather system will bring muggy weather with heat indexes — how hot it feels — near 100 degrees Saturday afternoon.
In addition, the forecast calls for occasional heavy rain with the possibility of thunderstorms through the weekend as Ela, which weakened to a "remnant low" Friday, passes north of the Hawaiian Islands.
A high-surf advisory remains in effect for the state’s eastern shores through 6 a.m. Sunday.
"Expect strong breaking waves and strong currents making swimming dangerous," said National Weather Service forecaster Peter Donaldson.
Surf ranging in heights from 6 to 8 feet rolled into eastern shores Friday.
Rainfall soaked some areas of Oahu, with nearly 21⁄2 inches falling in the Nuuanu area within the 24-hour period ending at 5 p.m. Friday. At the Oahu Forest National Wildlife Refuge in the central Koolaus, 3.6 inches fell in that 24-hour period, the most on the island.
The rain generated stunning waterfall displays in Nuuanu, Manoa and elsewhere.
A high temperature of 87 degrees in Hilo on Friday tied the record for the date, the National Weather Service said. The old record was set in 2008.
And rainfall in Kahului set a new record of 0.58 inch, breaking the old record of 0.21 inch set in 2002, the weather service said.
During this weekend, spotty downpours could produce up to 3 inches of rain within one hour, Donaldson said.
Conditions will vary as remnants of Ela, blocking tradewinds from the northeast, contribute to lighter wind over the islands, sticky humidity and rain.
Donaldson said light wind is expected Sunday over Kauai and Oahu.
Meanwhile the Central Pacific Hurricane Center is tracking two new tropical depressions that could strengthen on Saturday.
One is Tropical Depression 2C, about 480 miles south of Hilo with sustained winds of 35 mph, according to reports Friday evening. It was expected to turn into a tropical storm by Friday night or Saturday, pivot westward and slowly intensify.
The other, Tropical Storm Halola, was about 1,325 miles west-southwest of Hilo, with sustained winds of 40 mph.
Honolulu Emergency Management spokesman John Cummings III said the city is monitoring rain-prone areas such as Waiahole-Waikane for possible flooding.
With the hurricane season under way, Cummings advised having on hand enough food and water for at least seven days, along with medical kits and related emergency preparedness items. Should a hurricane strike the islands and knock out power, port and airport facilities, it could take at least a week to obtain emergency shipments from the mainland.
During a hurricane preparation meeting at the Waikiki Community Center on Friday, a Navy Region Hawaii official displayed disaster supplies ranging from a battery-powered or hand-crank radio capable of receiving weather alerts to an assortment of nonperishable food.
Michael K. Smith, director for training and exercises in emergency preparedness at Joint Base Pearl Harbor-Hickam, said a popular food item that seems to run out quickly at stores as people prepare for hurricanes is strawberry Pop-Tarts.
"You’ve got to think, ‘What do you want? What will last?’" Smith said.