Pouring out east, dry on the west

HOLLYN JOHNSON/Tribune-Herald Rain falls Tuesday in downtown Hilo, forming puddles in the Mo’oheau Bus Terminal parking lot.

HILO — A rainy February set records for parts of the Big Island, while other regions saw above-average totals.

But the west side of the island managed to escape the record start.

According to a National Weather Service precipitation summary, rain gauges at Pahala and Kapapala Ranch saw their highest February rain totals in more than two decades.

Pahala received 19.8 inches in February, more than 400 percent of its average February rainfall of 4.9 inches, and the highest total for the month since the gauge started recording rainfall amounts in 1991. Kapapala Ranch saw similar totals — 19.5 inches last month, also more than 400 percent of its monthly average — but its rainfall was the highest recorded for February since 1979.

Other gauges around the island saw above-average rainfall in February. The Hilo airport received 15.4 inches, or 162 percent of its 9.5-inch monthly average. The Kona airport received 258 percent of its 1.5-inch average with 3.8 inches recorded last month.

The highest deviation from the average occurred at the site of the Pali 2 rain gauge, which also saw the second-highest rainfall on the island last month — 30.5 inches, or 510 percent of its average — for an area that typically sees less than 6 inches of rain in February.

The highest rainfall last month, however, occurred at the Saddle Road Quarry, which received 38.9 inches. That total was a 375 percent increase from its monthly average. The quarry also has the greatest deviation from its average year-to-date rainfall, having received nearly 70 inches of rain so far this year, whereas it typically only receives 20.

While several locations on the windward side of the island have seen higher-than-average rainfall so far in 2018 — Hilo has received 160 percent of its average, Pahoa 200 percent, Mountain View 172 percent and Papaikou 133 percent — areas on the leeward and northern sides of the island are still below annual averages after a drier-than-usual January. Laupahoehoe, for example, has only received 86 percent of its average rainfall to date, while Honokaa has received 81 percent, Waimea 54 percent, Kealakekua 58 percent and Kamuela 45 percent. Mauna Loa, at 42 percent, has been the driest place on the island so far this year.

At the same time, Waikoloa has received more than double its typical rainfall to date, having been drenched by a total of 7 inches so far this year instead of its typical 3.3 inches.

Kevin Kodama, senior service hydrologist with the National Weather Service in Honolul, said March likely will see more ordinary rainfall as the “wet weather pattern” in which the state has been enveloped throughout February has moved west, beyond the islands.

Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com