It was an arid August on the Big Island.
Only three official rain gauges on the island logged more rain last month than in a usual August. Two are in Ka‘u: Kapapala and Kahuku ranches, with 3.67 and 3.09 inches, respectively — 13% above normal for Kapapala and 15% for Kahuku. The third is Kawainui Stream in the Pu‘u O ‘Umi Natural Area Reserve near Waimea, with 14 inches even, 57% higher rainfall than an average August.
“The dry conditions, combined with … extreme winds were some of the key factors that contributed to the devastating wildfires on the island of Maui on Aug. 8,” said Kevin Kodama, senior service hydrologist for the National Weather Service in Honolulu. The extreme winds between Aug. 7-9 were the product of Hurricane Dora, moving westward well to the south of the Island chain, interacting with a high-pressure system to the north.
“If we didn’t have the remnant of Fernanda go through, it would’ve been really dry,” Kodama noted.
The remnant low of the former tropical cyclone hit the island chain on Aug. 21. Automated gauges on the eastern side of the Big Island recorded 2 to 4 inches of rain, and east Maui gauges picked up 1 to 3 inches. There were no reports of significant flooding from this event.
Hilo International Airport received 5.35 inches of rain in August, almost half of its norm of 11.3 inches for the month. Despite that, most windward Big Island areas remain verdant.
“You see measurable rainfall almost every day but the amount is way down,” Kodama said. “This is the pattern when you get lower than normal rainfall, at least on the windward side. That’s been the case the past couple of months on the Hilo side.
“Conditions, especially lately, have been drying out. Stream flow has been dropping. Wailuku River and Honolii Stream have been dropping.”
Accustomed to aridity, Ellison Onizuka Kona International Airport in Keahole had the lowest rainfall total recorded for the month, 0.02 inches, just 4% of its August norm of 0.54 inches.
Kona has reported the return of volcanic haze, or “vog,” since Kilauea volcano on Sunday resumed erupting. It’s the third time this year Kilauea has been active.
All four of the official gauges in Kona’s coffee belt are also down from their usual August, although none appeared to be in drought status.
Waiaha’s 4.25 inches represents 90% of its normal August rainfall. Following closely were Kealakekua at 4.45 inches and Kainaliu at 4.34 inches. Both totals are 74% of an average August rainfall. And Honaunau, at 3.47 inches, tallied just 60% of its usual August rainfall.
“It is drier than usual. It has not affected the crops yet, which is really, really good,” said Bill Myers, CEO of Heavenly Hawaiian Kona Coffee Farm. “We’re having a solid year, and I think that’s true of our neighbors, as well.
“And after last year, we all needed it badly.”
Kodama predicted — with El Nino conditions and an upward trend in temperatures — for the dry weather to continue for the foreseeable future, including in the coffee belt.
“The forecast models from several months ago that predicted drying are turning out to be correct,” he said.
“With the volcano erupting again, the vog does not help boost rainfall. In fact, it does the opposite. And with them coming out of their summer wet season, it’s kind of a double whammy.
“It’s a good thing they got the rainfall that they needed earlier in the summer because there’s not much coming up over the next couple of weeks, at least.”
It’s still full steam ahead for the Coffee Love for Maui airlifts of ground Hawaiian coffee to first responders, health care workers and other disaster aid personnel on the Valley Isle. The airlifts, conceived by Helen Burnett, Heavenly Hawaiian’s workforce director, have unified most of the coffee farms to donate their product or other goods to the cause.
“It’s going great,” Myers said. “I think we have done five lifts at this point, all of them several hundred pounds. Some farmers are making their second donations. It’s taking on a life of its own.
“We’re getting a great response from the people over there. They’re very, very grateful.”
Myers said Burnett is in the process of arranging another airlift to Maui.
“Some of the aid workers are beginning to leave and we’ve still got a lot of coffee,” he said. “So we’ll be moving toward helping those who lost their homes and are staying at the churches and in the tiny houses that are being put up through the food banks.”
Kodama said the reduced rainfall, which is resulting in deteriorating pastures at leeward-area ranches, will likely hit the coffee growers at some point.
“There are starting to be impacts. We’re seeing the dropoff in rainfall is having an effect,” he said.
Email John Burnett at jburnett@hawaiitribune-herald.com.