As the remnants of Tropical Storm Niala made their way out of the state, the Big Island experienced some heavy showers, bringing flash floods and road closures in some areas Sunday night and early Monday morning.
The latest in a record-tying string of 11 storms to impact the Central Pacific this hurricane season, Niala continued to weaken Monday, being downgraded to a tropical depression by 5 a.m. and a “remnant low” as of 5 p.m.
At 5 p.m., it was about 315 miles southwest of South Point, with maximum sustained winds of 30 mph. The storm was moving west-northwest at 9 mph, according to the Central Pacific Hurricane Center.
The Monday afternoon notice said the post-tropical cyclone was expected to take a gradual turn toward the west-southwest and decrease in forward speed before “dissipation occurs on Wednesday,” according to a 5 p.m. update.
Hawaii Island remained under a high surf advisory until 6 p.m. Monday, with waves and surf of between 5 and 8 feet expected along the east and southeast facing shores.
From Friday at 8 a.m. to Monday morning at 8, the Hilo International Airport gauge measured a total of 4.86 inches of rain. Meanwhile, Piihonua amassed 11.33 inches, with 7.75 inches falling between Sunday and Monday, making it the rainiest location on the island during that 24-hour period. Waiakea Uka saw consistent heavy rain during the entire 72-hour period from Friday to Monday mornings, totaling 11.64 inches.
Saddle Quarry, located within the Hilo Watershed Forest Reserve about 16 miles mauka of Hilo, put up the biggest total during the weekend, with 16.21 inches of rain.
The heavy rains put the island under a flood watch, with flooding closing Kamehameha Avenue between Ponahawai Street and Pauahi Street, as well as Pauahi Street between Kamehameha Avenue and Aupuni Street, according to a 5:30 a.m. advisory from the Hawaii Police Department. The roads were opened again at 8:17 a.m., said a police spokeswoman.
The rainfall was in part because of a restoration of the trade wind pattern, according to National Weather Service hydrologist Kevin Kodama.
“The trades came back and we had a lot of shower activity,” he said. “We had pretty strong trades, and we had some of the outer rain bands as Niala passed to the south of the Big Island, causing rain.”
Kodama said he expected showers would continue this week, dropping to normal levels by midweek.
“It’ll still be a little bit rainy, but not quite like it was the last two or three days or so,” he said.
Email Colin M. Stewart at cstewart@hawaiitribune-herald.com.
