Add drought to the list of woes plaguing Hawaii in 2020.
After an unusually dry August that saw zero rainfall in some leeward spots and no storms during what is normally the peak month of hurricane season, 50% of the state is experiencing drought conditions, according to the U.S. Drought Monitor.
Maui County is suffering worst of all. Nearly all of the gauges across the four- island county recorded below-average rainfall last month — even at Puu Kukui in West Maui, one of the wettest spots in Hawaii, which posted its lowest August total since 1985.
“To be honest it’s pretty dismal, it’s pretty ugly right at the moment,” said Sumner Erdman, president of Ulupalakua Ranch, which manages 15,000 acres in southwest Maui, where there has been no measurable rainfall in the past six weeks.
Because of extremely dry conditions, 4,000 to 5,000 of those acres are unusable, he said, and the ranch has been forced to reduce its herds by shipping younger animals to be grown out on the mainland.
Drought also has brought water restrictions in parts of Maui and red-flag wildfire warnings across the state.
And there’s more bad news: “We’re not expecting the conditions to improve any time soon,” said Kevin Kodama, senior service hydrologist for the National Weather Service’s Weather Forecast Office Honolulu.
“We are still in the summer dry season, and what’s a little different is that even the windward areas are seeing some impacts,” he said. “You think that with persistent tradewind conditions, windward slopes would see showers, and they are, but the amount per day is low, so we’re starting to see signs of drought stress and stream flows are low.”
Kodama said lethargic tropical cyclone activity in the region is particularly notable, since August is historically the most active month for major storms in the central North Pacific basin. “However, there were no tropical cyclones during the entire month, and that doesn’t happen too often,” he said.
NOAA’s Central Pacific Hurricane Center in May forecast near- or below- normal tropical cyclone activity in the region during the hurricane season, from June through November, with predictions of two to six tropical depressions, named storms and hurricanes.
“Usually if you get that kind of range then you get at least one in August,” Kodama said. So far there have been just two for the entire summer: a system in June and Hurricane Douglas in late July, which didn’t bring as much rain as expected.
“You certainly don’t want direct hits, but even if you have a remnant or even if it misses, it pulls moisture up from the deep tropics. Then that will boost the rainfall — but we had nothing,” Kodama said.
“There was one in mid- August that tried to form far to the southeast that was never going to be a threat directly, but at least it would have been within the peak time of year. Once you get into September the numbers really start to trail off.”
THURSDAY’S weekly update of the U.S. Drought Monitor reported unfavorably dry conditions continuing across most of Hawaii, with “extreme drought” spreading to the western end of Molokai and southwestern Maui near Maalaea and along the leeward slopes of Haleakala.
Elsewhere, lower-level drought conditions occurred in the central and northwestern parts of other islands, the report said.
As for why Maui County is bearing the brunt of the drought, Kodama said Hawaii island’s massive profile to the southeast, with Mauna Kea and Mauna Loa, likely has been playing a role by blocking air flow.
“If you have normal tradewinds coming in from the east-northeast, then you’re going to get a better distribution of rainfall. But if the winds kind of switch a little bit, even become more straight east or slightly south of east, then the Big Island is going to have a bigger impact on Maui,” he said. “There are complex island interactions, and even subtle changes in the large-scale conditions can cause pretty substantial adjustments to the rainfall.”
The ongoing drought moved Maui officials last week to impose restrictions on nonessential water use until further notice for Upcountry and West Maui residents.
On the west side of the island, minimal rainfall in the mountains has reduced stream flows that provide most of the water supplied by the county water system.
Kauai has been the least impacted by drought this summer, according to the Drought Information Statement issued Wednesday by Kodama, although over the past month the island is trending toward moderate drought on its leeward side.
Moderate drought has expanded on Oahu, the report said, and now covers the southwestern half of the island with deteriorating conditions in the central and western portions.
The National Weather Service’s August rainfall summary noted the Waianae Range was especially dry, with several totals at less than 10% of the month’s average. On the windward side, Waimanalo reported its lowest August rainfall total since 1993, and on the town side of the Koolaus, Aloha Tower had its lowest amount since 2005.
On Hawaii island, moderate drought spread into the windward slopes from Laupahoehoe to Kilauea Volcano and covered most of South Kohala and leeward portions of North Kohala, Kodama’s drought report said. Ranchers have reported dry pasture conditions in Waikii and Mana, with degraded conditions over the eastern slopes of Mauna Kea and the lower slopes of the Kau District from Pahala to South Point.
Hamakua, from north of Hilo to Honokaa, hasn’t seen any appreciative rainfall for the past five weeks, “so it’s been really dry,” according to Mark Thorne, a range and livestock management specialist with the University of Hawaii’s Cooperative Extension Service.
“Conditions are getting pretty dire for a lot of ranching operations and having enough forage to carry their animals,” said Thorne, who works in Kamuela. Ranchers can sometimes manage short-term drought with a rotating grazing system, “but if it persists longer, then they will have to start weaning cows off sooner and shipping calves to relieve some of the pressure on forages.”
The situation is complicated by Hawaii’s limited slaughterhouse capacity, he said, and the fact animals can’t easily be moved to greener pastures around the islands or out of state.
“It’s a really big challenge to manage those herds,” Thorne said. “There’s a long-term impact to the industry if we’re in a long-term drought and ranches start to reduce herd size. Over time what happens when they do that is it can take up to five to 10 years to build herds back up.”
He said that before the current dry conditions, ranchers were just recovering herd numbers after a protracted drought that started in 2010 and lasted about seven years. Longtime ranchers told him it was the most severe drought they’d seen in more than 60 years.
“I don’t think we’re that far yet, but we’re not that far off either. If Maui doesn’t get some rain soon it’s going to get really bad for some parts,” Thorne said.
At Hawaii’s roughly 7,300 farms, orchards and specialty crops are particularly at risk from dry conditions, which can affect crop growth and quality in general.
Brian Miyamoto, executive director of the Hawaii Farm Bureau, said that so far the drought has been more difficult for ranchers than farmers, who can fall back on reservoirs and irrigation when rainfall is scarce.
“We have yet to see the huge impacts, but obviously a prolonged drought is extremely concerning to our farmers because water is critical for ag production,” he said. “So we are monitoring drought conditions.”
ULUPALAKUA Ranch, stretching from the lower slopes of Haleakala up to the 5,500-foot elevation, currently has 3,000 cattle, horses, sheep and elk, Erdman said. The property has been used for ranching since the late 19th century. Erdman’s father, C. Pardee Erdman, purchased the ranch in 1963.
“The upper grounds are still pretty good, but we’ve pretty much run out of feed below 1,800 feet,” Sumner Erdman said.
“We’re definitely moving animals around and trying to reorganize herds, but we are destocking as we speak, taking out younger animals and shipping them off to the mainland.”
To somewhat shield itself from the vagaries of nature, the ranch has been moving to diversify its interests, leasing land to the developers of a 21-megawatt wind farm that was completed in 2012. Erdman said a solar farm is another possibility, along with other agricultural activities — “but obviously that takes water.”
Like others who rely on the land for their livelihood, Erdman seemed resigned to current circumstances.
“Droughts can sear your soul, but I knew that when I came back and got into the business. It’s really part of my life and we just have to figure out how to deal with those things.”
The misery extends to small-scale ranchers on neighboring Molokai.
Jack Spruance runs the Molokai Livestock Co-op slaughterhouse and has about 10 head of cattle himself. He said the island’s dozen or so ranchers “are absolutely suffering.”
“We didn’t get the winter rains we should have gotten, especially on the west end, and it’s just gotten incredibly dry,” he said.
Tag-teaming with the drought to torment ranchers is Molokai’s wild deer population, Spruance said. “They take out your forage that you had saved for your cow herd, and when you get back to it, it’s not there,” he explained.
The slaughterhouse has been getting as many cattle as usual, but “they’re just incredibly thin most of the time.” That means lower- grade beef and less money for ranchers.
“I’ve been through two extended droughts during my time on Molokai, and in the late ’90s there was a pretty bad one that lasted three or four years,” Spruance said. “In terms of duration this is only getting started, but in terms of actual dryness, this is as bad as I’ve seen it.”
Unfortunately, below- normal rainfall is likely to continue in Hawaii for the early fall months, according to the Long-Lead Hawaiian Islands Outlook issued Aug. 20 by the NOAA Climate Prediction Center.
Barring any major storms passing near or delivering a direct hit, “leeward dryness will likely persist, resulting in a potential worsening and expansion of current drought areas across the state,” the report states.
“It’s still going to be dry for a while,” Kodama said. “I don’t think we’re going to transition until the later part of this year. We might get a slow start to the west season, which is normally October to April.”
The outlook also favors above-normal temperatures across the state through the rest of the year and into early 2021, due to a forecast of above-average sea surface temperatures around the Hawaiian Islands.
August rainfall totals for Select areas in Hawaii
Measured in inches
LOCATION August 2020 Average % Average
Oahu
Aloha Tower 0.14 0.97 14%
Ewa Beach 0 0.51 0%
Honolulu Airport 0.13 0.56 23%
Kahuku 0.46 2.44 19%
Upper Nuuanu 4.33 8.50 51%
Waimanalo 0.20 1.64 12%
Waianae 0 1.04 0%
Hawaii island
Hilo Airport 4.25 9.85 43%
Kahua Ranch 0.82 4.65 18%
Keahole Airport 0.53 1.39 38%
Laupahoehoe 5.56 12.62 44%
Mountain View 7.43 13.64 54%
Pahala 0.54 3.46 16%
LOCATION August 2020 Average % Average
Maui County
Hana 3.36 5.77 58%
Kahului Airport 0.03 0.50 6%
Kula 0.04 1.07 4%
Lahainaluna 0 0.82 0%
Maalaea 0 0.11 0%
Puu Kukui 10.89 33.56 32%
Wailuku 0.05 0.92 5%
Kaunakakai 0 0.45 0%
Lanai City 0.54 1.31 41%
Kauai
Hanapepe 0.53 1.51 35%
Lihue Airport 1.28 2.13 60%
Waialeale 27.24 34.81 78%
Wainiha 4.16 8.30 50%
Source: National Weather Service Honolulu