Big Island’s coffee belt sees record rainfall in August

August was a very wet month for the Kona coffee belt.

According to the monthly rainfall summary from the National Weather Service in Honolulu, all four gauges in the coffee belt region recorded more than 10 inches of rain last month. That’s more than the 9.4 inches of rain recorded in August at Hilo International Airport.

In fact records for the highest rainfall total in August were broken at Kealakekua and tied at Honaunau with 14.54 inches and 10.34 inches, respectively, almost 2 1/2 times the average August rainfall of 6.05 inches in Kealakekua and almost twice the usual August rainfall of 5.83 inches in Honaunau.

NWS hydrologist Kevin Kodama cautioned, however, there may have been rainier years in the past, as records in those two sites go back less than three decades, “maybe 27, 28 years.”

Waiaha, on the slopes of Hualalai in North Kona, recorded the highest rainfall total of any Big Island spot for the month, 15.96 inches, more than three times its August average of 4.71 inches. The fourth coffee belt rain gauge, in Kainaliu, South Kona, weighed in at 10.34 inches, almost twice its 5.83 August average.

“I don’t think it will be their wettest wet season,” Kodama said Friday. “Back in 2015, September was really wet for the Kona side. A lot of the wet season records were broken for Kona in 2015, but that was not so much because of August rainfall, but because of September rainfall.”

Karen Zulkowski, of Kenai Koffee in Captain Cook and secretary of Kona Coffee Farmers Association said the abundance of rainfall is a mixed blessing for coffee farmers.

“We have a lot of ripe (coffee) cherry, but people are having problems getting out picking. The trees themselves are very happy,” Zulkowski said. “The coffee crop itself is pretty set, but the problem is, the tree branches can get pretty heavy and crack under the weight. But the trees are very healthy this year, after the vog from last year and the crop looks really good.”

Kona locations outside the coffee belt also saw substantial rainfall last month. Puuwaawaa measured an eye-popping 10.4 inches, almost nine times its August average of 1.18 inches, and almost a third of its year-to-date total of 28.4 inches, which is almost twice its average precipitation for the first eight months of the year. Puuanahulu checked in at just above four inches of rain, more than thrice its August average. It’s year-to-date total of 20.97 inches is almost three inches above the norm.

All Kona locations monitored by the weather service are reporting above average rainfall both for the month and for the year, as well, except one — Ellison Onizuka Kona International Airport at Keahole.

The always arid airport on the leeward side received 1.13 inches in August, 81% of its usual 1.39 inches for the month. It’s been an unusually dry year there, as well, with the airport gauge tally a mere 6.2 inches for the year, 51% of its usual 12.11 inches.

Ka‘u, which stakes its own territorial coffee claims, also saw some impressive August rainfall totals.

Kapapala and Pahala both received about twice their usual August rainfall, with 7.14 inches and 6.84 inches, respectively. Kapapala’s year-to-date total of 37.65 inches is 11% above its norm for the first eight months, while Pahala is right at 100% of average at 33.85 inches.

And while even South Point had higher-than-average rainfall in August, with 3.45 inches, that may not be able to pull it out of drought condition. Ranchers in North Kohala are also hoping for some higher rainfall totals. The last drought information statement issued by NWS on Aug. 15 contained this less-than-optimistic outlook: “According to the U.S. Department of Agriculture’s Farm Service Agency, ranchers operating in the South Point area have seen modest improvement in pasture conditions from rainfall over the past month.

However, follow-up rainfall is needed for continued recovery. On the opposite end of the island, satellite-based vegetation health data indicated that conditions in the Hawi and Upolu Point areas worsened over the past month.”

Windward Big Island rain gauges were near average at most locations, Kodama said. Hilo airport was at about 95% of its norm for the month, but its year-to-date total of 57.39 inches for the year is just 72% of its norm of 79.94 inches.

Mountain View tallied 12.39 inches last month, 91% of its average, while Piihonua measured 13.39 inches, about 86% of norm and Pahoa exceeded its usual August rainfall with 11.44 inches. And while the rainfall picked up for most windward spots in August, all three spots are lagging behind their year-to-date norms.

That said, September has started off with some heavy, if brief, showers on the windward side.

“I think, at least for now and for maybe the next couple of weeks, it looks like we’ll have the usual windward showers,” Kodama said. “And quite honestly, I was expecting most of the summer to be like how it is now. But it hasn’t. This summer has been pretty erratic. Some of that is due to abnormal trade winds. … They’ve been coming in a different direction than normal and causing changes in rainfall distribution. … But from later August to the current time, we’ve been picking up a little more normal trade wind direction and speed. So that’s been helping with the rainfall.”

And while a tropical storm, Akoni, formed last week in the Central Pacific far south of Hawaii, it weakened quickly and was listed as just a disturbance by late Friday afternoon and was expected to have no effect on Hawaii’s weather.

“The two earlier cyclones, Erick and Flossie, they were, like, glancing blows,” Kodama said. “They brought some rain to the Big Island, but I was expecting more windward rainfall because the ocean temperatures have been so warm.

“For the Kona side, it’s translated to more rain, but it hasn’t for the Hilo side or for most of the windward side.”

Email John Burnett at jburnett@hawaiitribune-herald.com.