Forecasters are predicting a mild reprieve from the record-setting rain that soaked sections of the Big Island this weekend, causing flooding, rock slides and road closures in windward areas.
“It’s definitely not drying out by any stretch. It’s just that the rain rates are a little bit lower,” Derek Wroe, forecaster for the National Weather Service in Honolulu, said Monday.” Unfortunately, it’s going to stay that way for the next couple of days. So, I don’t really see a whole lot of improvement over the short term.
“I see some drying starting Wednesday. And by Thursday, we’ll be into some breezy trade winds. There’ll still be some showers moving through. They just won’t be as frequent.”
According to Wroe, Hilo International Airport received 11.13 inches of rain on Saturday, washing away the previous record for Feb. 18 of 8.61 inches set in 1951.
Through Sunday, Hilo had recorded 28.32 inches so far this month, almost three times the average rainfall of 10.22 inches the airport normally receives for all of February.
“It wasn’t a front that came through,” Wroe said. “It was a wet and moderately unstable pattern that set up over the region. And the Big Island was in the worst place, especially for the windward and southeast slopes. That’s where the most rain, by far, fell across the state.”
Those southeastern slopes Wroe referred to were hit particularly hard.
During the 24-hour period ending at 8 a.m. Saturday several gauges in that area tallied multiple inches of rainfall, including Kapapala Ranch, 9.79 inches; Pahala, 5.65 inches; Lower Kahuku, 6.14 inches; and Kahuku Ranch, 2.63 inches.
That deluge caused flooding in the Kawa Flats area of Ka‘u between the 56- and-62-mile markers of Hawaii Belt Road (Highway 19) and also caused closures of Wood Valley Road in Pahala and Kaalaiki Road, also known as Old Cane Haul Road, in Naalehu. A driver had to be rescued Saturday from a normally dry riverbed in Wood Valley that became swollen by the floodwaters.
Many of those road closures continued into Sunday. Highway 11 in the Kawa Flats area and Wood Valley Road were closed again late Monday afternoon.
Puna was wet, as well. During that 24-hour period, Mountain View received 7.03 inches of rain and Pahoa measured 3.59 inches.
It’ll continue to be wet in East Hawaii. The NWS extended forecast predicts rain and possibly thundershowers in the Hilo area today.
“We’re going to get some thunderstorms over the interior and leeward sections of the Big Island,” Wroe said. “There’ll be some thunderstorms and locally heavy stuff. It’s going to be more of a widespread shower on the leeward side.”
Rainfall totals between three-quarters of an inch and an inch are predicted for Hilo today, tonight, Wednesday and Wednesday night. Rain also is predicted for later this week and the weekend, but the forecast has no predictions as to how much is likely to fall.
Ellison Onizuka Kona International Airport in Keahole, which has received just 0.79 inches of rain this month — most during this past weekend — also has rain in its forecast, but mostly between a tenth and a quarter inch on a given day or evening.
“The rain will be focused mainly over the windward areas,” Wroe said. “Kona will get theirs mainly in the afternoon hours, if you get a little bit of heating on the slopes.”
Email John Burnett at jburnett@hawaiitribune-herald.com.
