The April showers that failed to materialize in East Hawaii went mostly missing in May as well.
The majority of gauges along the Big Island’s windward slopes “recorded below average rainfall totals for the month of May,” according to the monthly rainfall summary published by Kevin Kodama, a National Weather Service senior hydrologist in Honolulu.
Still, largely because of what Kodama called “the wettest March in over a decade,” the year-to-date rainfall totals for Big Island gauges in populated areas are at or above normal levels.
Hilo International Airport measured only 3.45 inches of rain in April, less than half of its normal total, but at 60.7 inches for the first five months, the airport is still 17% above its yearly average.
The same trend held for Waiakea Uka, which received 8.18 inches, well under it’s 14.5 inches average for May, but is still above average for the year with just more than 87 inches of rain.
Always rainy Glenwood was also less so than usual, with 8.6 inches last month, 54% of its 15.9 inches norm. The 96.13 inches year-to-date yearly total is about 2 1/2 inches below the norm for the Puna rain forest village.
Honokaa had a wetter-than-normal May at just less than 9 inches of rain and is about 10% above its yearly average, with almost 54 inches for the first five months.
Kodama noted “declining pasture health in the Hamakua and South Kohala areas” reported by the Farm Service Agency, which he said is “consistent with rainfall and satellite-based vegetation health data.” He added the low May rainfall totals will “increase water-hauling for personal needs due to insufficient supply from water catchment systems.”
“Low surface water flows are also starting to impact aquaculture operations in the Hilo area,” Kodama said.
Waimea is at about 85% of normal rainfall for May, at 3.4 inches, and for the year, at 25.9 inches.
Ellison Onizuka Kona International Airport reported 2.58 inches of rain for the month, 29% higher than its normal 2 inches. The usually sunny airport measured 6.82 inches for the year, 75% of its average of slightly more than 9 inches for the first five months.
Three of the four Kona coffee-belt rain gauges, Waiaha, Kealakekua and Honaunau, all had above average May totals at 11.44 inches, 8 inches and 7 inches, respectively. For Waiaha, that’s more than twice the normal May rainfall. The fourth gauge, at Kainaliu, tallied 4.3 inches, about 83% of its norm.
All four spots have received above normal rainfall for the year, with Waiaha at more than twice the norm, and are entering the summer rainy season for the leeward slopes.
Ka‘u tallied mostly above average rainfall totals for May as well, with 3.47 inches at Pahala and Kapapala and 7.06 inches at Kahuku Ranch. Kapapala’s year-to-date rainfall total of 47.8 inches is almost twice the norm, while Pahala has more than 1.5 times its average for the first five months at 38.26 inches, as does Kahuku at 24.42 inches.
Email John Burnett at jburnett@hawaiitribune-herald.com.