While most of East Hawaii is seeing a wetter-than-average year so far, much of West Hawaii is parched.
That’s particularly true for the Kona coffee belt — potentially bad news for this year’s coffee crop — according to the June rainfall report released Thursday by hydrologist Kevin Kodama at the National Weather Service’s Honolulu office.
The rain gauge in Kealakekua measured just 1.76 inches for June, less than a third of its normal 6.05 inches, and “its lowest June since 2004,” Kodama wrote. Rainfall there for the year in was 14.34 inches through June, about 55 percent its usual total of 25.93 percent.
“The leeward side, especially Kona, was a little surprising — because this time of year, the Kona slopes, the Kona coffee belt, it’s their wet season,” Kodama said. “It’s the only leeward area in the state that has a summertime rainfall maximum. So they should’ve had an uptick in rainfall, especially with the oceans being a little bit warmer, but they’re actually pretty dry. I think that might be an effect of the volcano, because you have a lot more vog being produced right now. That actually has an effect of decreasing rainfall, because you’ve got a lot more particulates in the air.”
Kodama explained that moisture in the air partially condenses on vog particulates and evaporates, with less rising and condensing into rain clouds.
Other leeward rain gauges showing an unusually dry year include Ellison Onizuka Kona International Airport in Kailua-Kona, with 6.25 inches, 62 percent of its usual total of just over 10 inches and Kainaliu, with 13.2 inches, 53 percent of its norm of 24.77 inches. Honaunau, also in the coffee belt, is doing somewhat better, with 21.86 inches, 86 percent of its average of 25.52 inches.
Bill Myers, general manager of Heavenly Hawaiian Kona Coffee Farms in Holualoa said the company’s upper farm, at 1,200 feet in elevation “has had enough rain. We’re fine; no problem.” However, at their lower farm, which is at 800 feet, “rain has been too light.”
“What we’re doing now, on an emergency basis, we’re upgrading our irrigation system,” Myers said. “Because what you’ll find, when you don’t have proper rain, the coffee beans will hollow out. They’ll be there. They’ll turn red, but there will be nothing valuable inside. So we have to get the irrigation in place. This is the first time we’ve had to do this in many years. And what we’ve done, our answer — and we literally started today, is to get our irrigation up to snuff so we don’t lose our crop.
“We get the good coffee because we’re right in the rain shadow of the mountain. Our little ecosystem gives it to us. But this year, with the lower elevations, not so much. And it’s not as if this is a year where we needed more challenges.”
Myers said he’s also concerned about the increased vog being experienced in Kona because of Kilauea’s lower East Rift Zone eruption, which began May 3.
“It’s not just the affect of the acidity of the vog, it’s the sunlight. We need sunlight,” he said. “It’s what’s going to ripen up the crop. And we’re waiting to see if that’s going to have an effect. So far, no negative effects that we can perceive, but everybody’s watching it real closely. And we’re always fighting the (coffee berry borer) beetle. So we don’t need the additional challenge, and it looks like, just like everyone else on the island, it looks like this is the year we do get challenges.
“Here’s what we think is going on with the vog. If it had come earlier, if it had come during the flowering, it might have affected our crop in a serious way. But thank God it didn’t. It came later. It came after the flowering, when the cherries were formed and they were beginning to grow and ripen. At this point, we believe they’re safe. And we’ve walked our fields, we checked the cherry. We haven’t seen any damage.”
Myers said Kona coffee farmers deal with “vog every year but not in this abundance.”
“It’s a crazy situation over here,” he said. “We had early rains, so we got very, very early flowering. So we’re seeing cherry ready to pick now. … That’s a month early. This is a very strange year that we’re facing.”
Ka‘u coffee farmers also saw a downturn in June rainfall, although for the year, the Ka‘u coffee belt is wetter than normal. Vog is the likely culprit there, as well, as Pahala has experienced not only gas emissions from the lower East Rift Zone, but ash from Kilauea’s summit explosions.
Pahala had just 0.59 inches of rain in June, less than a third of its usual 2.06 total for the month. In May, Pahala received 1.52 inches, less than half of its normal monthly total of 3.13 inches. For the year, however, the former sugar plantation village has measured 38.8 inches of rainfall, 44 percent above its norm of 26.9 inches. The year-to-date total is deceptive, however, as almost half of the rain Pahala has received this year came within a 28-day period — February, when a mind-boggling 19.89 inches of rain deluged the picturesque town.
“We need rain,” said Lorie Obra, owner of Rusty’s Hawaiian, whose Pahala coffee farm is at about 1,800 feet in elevation. “We don’t really have any irrigation here; we depend on the rain.”
Obra said the vog and ash fall is “not really affecting us that much right now.”
“There are some flowers that get burnt …,” she said. “We just really wish that the vog and the ashes would stop. We don’t know the long-term effect it will give to the plants. Right now, we might not be seeing it that much, but we don’t know.”
Kapapala Ranch in Ka‘u — which saw just 0.45 inches in June, less than a quarter of its norm — is having an even wetter year, so far, with 43.22 inches, 163 percent of its average of 26.53 inches. Like Pahala, more than 19 inches of that total fell in February.
East Hawaii, which is experiencing a wet 2018, “had near to above average rainfall for the month of June,” Kodama wrote. “The Pahoa gauge posted its highest June total since 2005.”
Pahoa tallied 9.35 inches of rain in June, 107 percent of its 8.75 inches June average rainfall. Pahoa’s yearly total as of June 30 was 98.84 inches, a whopping 51 percent increase over its average of 65.30 inches. Given Monday’s freak thunderstorm July 2 over Kilauea’s lower East Rift Zone, it’s known volcanic activity can affect weather, but Kodama doubts the events in Leilani Estates subdivision and downslope in lower Puna had an effect on last month’s rainfall in Pahoa.
“Pahoa’s not downwind of the volcano,” Kodama explained. “If you look at other places around Hilo, the windward side has been pretty wet, and that’s been consistent with what we’re expecting for this summer. Because of the warm sea temperature, the climate models have been predicting wetter-than-normal conditions. In the summertime, that manifests itself on the windward slopes.”
Hilo International Airport measured 74.13 inches of rain through June, 125 percent of its 59.28 inches norm. Hakalau had 54.37 inches for the year, 50 percent higher than its average of 36.33 inches. Mountain View also has had well-above-normal rainfall, just over 111 inches — 132 percent of its 84.07 inches norm. One windward spot down somewhat is Laupahoehoe. The gauge there recorded 64.29 inches of rain, just 87 percent of its usual 74.1 inches. Glenwood, in the heart of the upper Puna rainforest, also is down, but slightly, at 113.34 inches, 98 percent of its norm of 115.92 inches.
Email John Burnett at jburnett@hawaiitribune-herald.com.