State of Hawaii

MONTH: June 2009

PREPARED: July 6, 2009

State: [Text data table for rain gages]

Following an unusual May, the weather pattern during the month of June appeared to be more typical of the warm season as trade winds dominated conditions over and around the Hawaiian Islands. Trade wind speeds even reached fresh to strong levels from June 21 through 23 before easing back into the moderate to fresh range. There were no heavy rain events in June, but the resumption of trades brought much needed rainfall to windward areas of the state.

Leeward areas, especially on Maui and the Big Island, did not receive much rainfall and remain under drought conditions. On June 25, the Maui County Board of Water Supply requested a 5 percent voluntary cut-back on water use for Upcountry Maui residents due to diminishing reservoir water levels. Pasture conditions have also been deteriorating on portions of all the islands and impacts to livestock operations have been increasing.

Island of Kauai : [June 2009 map] [Year-to-date map]

Most of the rain gages on Kauai indicated below normal rainfall totals for the month of June. The sole exception was the gage at Kapahi which indicated a near normal total of 3.83 inches (96 percent of normal). Most of the remaining totals fell within the range of 30 to 60 percent of normal. The resumption of trade winds translated to the resumption of rainfall at the summit of Mount Waialeale with the U.S. Geological Survey (USGS) gage at the summit posting a monthly total of 20.14 inches (67 percent of normal). The total allowed Mount Waialeale to reclaim its place as the wettest spot in the State of Hawaii following a record dry May. While not record-setting, Lihue Airport’s monthly total of 0.54 inches (30 percent of normal) represented the fourth driest June since site establishment in 1950.

Most of the gages on Kauai continued to indicate below normal totals for 2009 through the end of June with the majority within the range of 40 to 60 percent of normal. Mount Waialeale’s 136.40 inches (64 percent of normal) remained the highest year-to-date total in the state by a large margin.

Island of Oahu: [June 2009 map] [Year-to-date map]

Most of the rain gages across the island of Oahu recorded below normal rainfall during the month of June. West Oahu was especially dry with most totals at less than 20 percent of normal. The U.S. Fish and Wildlife Service’s Oahu Forest National Wildlife Refuge (NWR) gage posted the highest monthly total of 10.36 inches (68 percent of normal), though the USGS’ Poamoho No. 2 gage recorded the highest daily total of 1.51 inches on June 26.

Maui County: [Maui June 2009 map] [Year-to-date map] [Molokai/Lanai June 2009 map] [Year-to-date map]

Most of the rain gages across Maui County recorded below normal totals for the month of June. Central and west Maui and western Molokai were especially dry with most totals coming in at less than 25 percent of normal. The USGS gage on Puu Kukui recorded the highest monthly total of 16.84 inches (64 percent of normal) and the highest daily total of 2.89 inches on June 18. The return of trade wind showers helped push some of the east Maui (e.g. West Wailuaiki and Oheo Gulch) totals to near normal levels.

Island of Hawaii: [June 2009 map] [Year-to-date map]

The resumption of trade wind rainfall helped boost eastern Big Island rain totals into the near to above normal range for the month of June. However, leeward areas continued to see very dry conditions with most sites reporting less than 50 percent of normal rainfall during the month. The Glenwood rain gage recorded the highest monthly total of 12.81 inches (175 percent of normal). However, the highest daily total occurred at the Waiakea Uka gage, which recorded 2.13 inches on June 22. Mountain View received more than one inch of rain on 4 out of 5 days from June 22 through June 26.

Data Sources: Data used in this report are largely from National Weather Service sources including climate network weather observation stations at Lïhue, Honolulu, Kahului, and Hilo, the Hydronet state network of automated rain gages, and selected Cooperative Observer sites. Additional data come from automated rain gages operated by the State of Hawai‘i Department of Land and Natural Resources, the US Geological Survey, the US Bureau of Land Management, the US National Park Service, the Department of Defense, and the US Fish and Wildlife Service. Data presented here are not certified and should be used for information purposes only.

Kevin R. Kodama
Senior Service Hydrologist
NOAA/NWS Weather Forecast Office Honolulu