MONTHLY PRECIPITATION SUMMARY State of Hawaii portion of Honolulu HSA MONTH: June 1999 PREPARED: 12 July 1999 State: No flash flood warnings were required or issued during June. Trade winds prevailed throughout the entire month of June at mostly light to moderate intensities. Trade wind showers were present across the region on a consistent basis, but totals were generally light statewide. The lack of significant rains over portions of the islands of Hawaii and Maui helped worsen an ongoing rainfall deficit that can be traced back to the 1997/98 El Nino event. Island of Kauai: While rainfall was mainly light over Kauai it occurred on a consistent basis. For example, the gage at Hanalei reported measurable rain on 90 percent of the days for a total of 4.97 inches, or 94 percent of normal. Three sites (Kokee, Kapahi, and Wailua) reported amounts at or above normal and three others (Hanalei, Omao, and Kalaheo) observed totals between 90 and 100 percent of normal. A note of caution regarding the Lihue Variety Station data. While rainfall data were reported throughout the month, a 28 percent of normal value looked suspiciously low relative to the other sites. For the year, rainfall totals remain below normal across the island, mainly in the 60 to 85 percent of normal range. Island of Oahu Oahu fared quite well during June with respect to rainfall. All gages along the windward side and interior valleys of the Koolau Range reported greater than 50 percent of normal rainfall for the month. Five gages in central Oahu (Wheeler AFS, Mililani, Waiawa, Palisades, and Waipio) reported above normal rainfall. As is usual for a trade wind weather pattern, the highest observed value for the month was at the Manoa Lyon Arboretum site with 9.77 inches, or 84 percent of normal. The largest positive anomaly was at Mililani with its 2.67 inches being 157 percent of normal. Consistent with the presence of persistent trades, all leeward sites showed below normal rainfall. Gages at Waianae and the Honolulu Airport recorded only 0.07 and 0.11 inches, respectively. While the Airport had a dry month, the data show that through the first six months of the year, rainfall (5.93 inches) has already exceeded last year's record-breaking annual total of 4.52 inches. Maui County Dry conditions persisted over most areas of Maui County during June. The central valley of Maui and the Makawao region upslope have been especially dry with three gages in the area (Waikapu Country Club, Kihei, and Pukalani) recording zero rainfall through the month, and the gages at Kula and Ulupalakua recording only 0.01 and 0.03 inches, respectively. The persistence of dry conditions in this area has forced the local government to place mandatory restrictions on water use. Conditions were better over windward areas of Maui where rainfall totals were 69 to 87 percent of normal. The three gages spread across the islands of Molokai and Lanai all reported below normal rainfall as well. Island of Hawaii: June was relatively dry for the island of Hawaii as well. The gage at Glenwood was the only site to report above normal rainfall (7.83 inches, 107 percent of normal). The remaining sites were mainly in the 50 to 75 percent of normal range. The Kau region was very dry with totals of only 9 and 15 percent of normal recorded at Pahala and Kapapala Ranch, respectively. The Kamakoa gage in leeward Kohala showed the lowest rain total at 0.01 inches (3 percent of normal). Although June was relatively dry for the island, year-to-date totals remained at or above normal for most of the sites in the Hilo and Puna areas due to the very wet conditions experienced during January through mid-April. THE FOLLOWING LIST CONTAINS RAINFALL STATISTICS FOR SELECTED LOCATIONS FROM AROUND THE STATE. THE FIRST COLUMN IS THE OBSERVED RAINFALL FOR JUNE. THE SECOND COLUMN IS THE 30-YEAR AVERAGE FOR THAT LOCATION WHILE THE THIRD COLUMN LISTS THE PERCENT OF AVERAGE RAINFALL FOR THE MONTH OF JUNE. THE FOURTH AND FIFTH COLUMNS ARE THE YEAR-TO-DATE TOTAL AND THE PERCENT OF AVERAGE, RESPECTIVELY. YTD KAUAI JUNE AVG %AVG YTD %AVG LIHUE AIRPORT 1.47 1.7 86 15.75 73 HANALEI 4.97 5.3 94 37.42 61 HANAPEPE 0.72 1.0 72 11.07 70 OAHU HONOLULU AIRPORT 0.11 0.5 22 5.93 53 MANOA ARBORETUM 9.77 11.7 84 72.39 97 NIU VALLEY 1.30 1.5 87 13.77 65 WAIHEE PUMP 2.73 4.0 68 29.22 54 LUALUALEI 0.46 0.8 57 7.60 55 WAIALUA 0.35 0.9 39 9.11 49 MOLOKAI KAUNAKAKAI 0.22 0.3 73 3.95 39 LANAI LANAI CITY 0.42 1.4 30 8.44 39 MAUI KAHULUI AIRPORT 0.09 0.3 30 6.55 52 HANA 2.64 3.8 69 N/A N/A HAIKU 2.85 3.4 84 N/A N/A KIHEI 0.00 0.1 0 2.13 22 LAHAINALUNA 0.15 0.2 75 4.11 34 WAILUKU 0.25 0.4 63 7.13 41 HAWAII HILO AIRPORT 1.47 6.2 24 68.50 105 PAHALA 0.20 2.2 9 12.34 40 HONAUNAU 2.87 7.0 41 11.30 35 KAMUELA (UPPER) 2.24 3.0 75 31.14 98 GLENWOOD 7.83 7.3 107 122.19 136 LAUPAHOEHOE 3.30 6.2 53 62.11 75 Data Sources: First order climate network weather observation stations of the National Weather Service at Lihue, Honolulu, Kahului, and Hilo, HI. Additional data were taken from the Hydronet state network of automated rain gages. Data collected in the automated gages are not certified and information used above should be used for information purposes only. Kevin R. Kodama, Senior Service Hydrologist National Weather Service Forecast Office Honolulu, Hawaii