A strong kona low developed northwest of the main Hawaiian Islands and produced heavy rainfall and strong winds over many areas of the state. The main rain band hit the Big Island first on Sunday, December 5, then shifted slowly westward across the island chain over the next two days. Rainfall totals were greatest over the southeastern flank of the Big Island, the south- and west-facing slopes of Haleakala, and most of Oahu, with the peak day of rainfall occurring on December 6.
Flooding impacts on the Big Island were minimal on December 5, but increased on December 6 as rainfall increased in intensity and coverage. Several normally dry gulches in the Kau District flooded, and Highway 11 closed at Kawa Flats for a few hours. Persistent heavy rainfall initiated over Maui on the afternoon of December 5 as a north to south oriented rain band hit the slopes of Haleakala. Large flash floods filled the normally dry gulches west of Kaupo and closed Piilani Highway. Severe flooding also occurred in the Maui Meadows subdivision, causing damage to homes and washing away several vehicles. Roads in the Kula area were also closed due to flooding.
On the afternoon and evening of December 6, thunderstorms with heavy rainfall moved over Oahu from the south, causing flooding in numerous locations across the south side of the island and especially from Pearl City to Kahala. One notable impact was flooding damage to the Iwilei power substation which cut electrical service to Downtown Honolulu businesses and residents. Also, a section of H1 westbound through Honolulu was closed due to waist-deep water near the Vineyard offramp. On the windward side of Oahu, flooding closed Kamehameha Highway from Waiahole to Waikane. The island of Kauai managed to avoid significant flood impacts during the entire event.
Strong southerly winds also accompanied the kona low, causing damage and power outages. Winds were strongest on the Big Island on December 5, with reports of large trees blown down blocking roads. There were power outages from Volcano to lower Puna District, with the greatest impacts in lower Puna. The strong winds spread westward across Maui County and Oahu the evening of December 5 and into the morning of December 6. Trees and power lines were blown down in Kula and Keokea on Maui, and on Oahu the Honolulu Fire Department responded to multiple reports of downed trees, downed power lines, and damaged roofs. At Honolulu Airport, two planes were damaged when an empty storage container was blown into them. As with rainfall, the island of Kauai also managed to avoid significant wind impacts as well.
In addition to the peak wind gusts across lower elevations on December 5-6 listed in the table below, higher elevations received their strongest winds on Saturday, December 4. The strongest gusts measured on Mauna Kea Summit were at the Canada France Hawaii Telescope, where an anemometer measured multiple gusts over 100 mph midday Saturday; the highest was 105 mph at 1:49 pm. On Maui, rangers at Haleakala National Park measured a gust to 93 mph around 11 am Saturday. Road crews on Mauna Kea reported snow drifts of 3 to 5 feet when they were able to return on Tuesday, December 7, and estimated that 6 to 10 inches of snow fell during the blizzard event.
The following are selected rainfall totals for the 3-day period (72 hours) ending at midnight HST, Wednesday, December 8. All amounts are in inches. These totals are considered preliminary for information purposes only.
Location 3-day total Kauai Omao 4.78 Kapahi 4.68 Lihue Airport 3.83 Oahu St. Stephens Seminary 12.83 Maunawili 12.61 Nuuanu Upper 12.45 Luluku 11.94 Manoa Lyon Arboretum 11.89 Waihee Pump 11.36 Moanalua 11.22 Makua Range 10.95 Ahuimanu Loop 10.86 Dillingham 10.12 Ewa Beach 9.57 Palisades 9.44 Aloha Tower 9.38 Honolulu Airport 9.28 Waianae 8.56 Maui County Kula 1 12.89 Puu Alii (Molokai) 9.28 Puu Kukui 7.25 Ulupalakua 6.98 Lanai 1 6.55 Kepuni 5.73 Lahainaluna 5.51 Kula Branch Station 4.58 Kahului Airport 3.48 Big Island Nene Cabin 14.26 Keaumo 13.42 Pali 2 11.64 Kulani NWR 11.15 Hilo Airport 5.77
Note that credible rainfall estimates from the Multi-Radar, Multi- Sensor (MRMS) system showed more than 20 inches of rainfall on Maui along the south-facing slope of Halekala over the Kahikinui Forest Reserve.
Strongest wind gusts from Sunday 12/4 to Monday 12/5: Location Speed Time/Date ...Kauai... Lihue Airport 29 MPH 0653 PM 12/05 ...Oahu... Kuaokala 58 MPH 0236 AM 12/06 Makapu'u Beach 50 MPH 0234 AM 12/06 Honolulu Harbor Pier 1 49 MPH 1105 PM 12/05 Makua Range 45 MPH 1258 AM 12/06 Palehua 42 MPH 1136 PM 12/05 Kalaeloa Airport 41 MPH 1132 PM 12/05 Kailua 40 MPH 0336 AM 12/06 Schofield Barracks 40 MPH 0157 PM 12/06 Honolulu Airport 38 MPH 1113 PM 12/05 Kaneohe Mcas 38 MPH 0339 AM 12/06 Schofield East 38 MPH 0258 AM 12/06 Dillingham 37 MPH 0349 AM 12/06 Oahu Forest NWR (USFWS) 36 MPH 1136 PM 12/05 Laniakea 35 MPH 0305 AM 12/06 Kahuku Training Area 33 MPH 0159 AM 12/06 Pearl City 33 MPH 1117 PM 12/05 Wheeler Air Force Base 33 MPH 0142 PM 12/06 Laie 32 MPH 0137 AM 12/06 Mokuleia 32 MPH 1127 AM 12/06 Waianae Valley 32 MPH 0237 AM 12/06 Punalu'u 29 MPH 1050 AM 12/06 ...Maui County... Kula 1 64 MPH 0648 PM 12/05 Kanaha WF 55 MPH 0957 PM 12/05 Kaneloa 55 MPH 1054 PM 12/05 Lanai 1 52 MPH 0837 PM 12/05 Kahului Airport 51 MPH 0956 PM 12/05 AH6GR Maui 47 MPH 1045 PM 12/05 Lanai Airport 47 MPH 0748 PM 12/05 Molokai Airport 43 MPH 1126 PM 12/05 Kealia Pond (USFWS) 42 MPH 1020 PM 12/05 Puu Alii 32 MPH 0922 PM 12/05 ...Big Island... Kailua Kona Airport 53 MPH 0753 PM 12/05 Kahuku Ranch 50 MPH 0529 PM 12/05 Pali 2 48 MPH 0601 PM 12/05 Kaupulehu 45 MPH 0936 PM 12/05 Mauna Loa 45 MPH 0534 PM 12/05 PTA West 45 MPH 0956 PM 12/05 Kaloko-Honokohau 41 MPH 0415 PM 12/05 PTA Range 17 41 MPH 0549 PM 12/06 Puho CS 39 MPH 0322 PM 12/05 Puuanahulu 39 MPH 0837 PM 12/05 Puuwaawaa 39 MPH 0937 PM 12/05 Nene Cabin 38 MPH 0823 PM 12/05 PTA East 38 MPH 0859 PM 12/06 Pahoa 35 MPH 1031 AM 12/05 Hilo 31 MPH 0309 PM 12/05 Hilo Airport 30 MPH 1233 PM 12/05 Waikoloa 29 MPH 0835 PM 12/05 Hilo (NOS-NWLON) 27 MPH 0300 PM 12/05 Lower Kahuku 27 MPH 0623 PM 12/05 Kapapala RAWS 26 MPH 0348 PM 12/05 ...Maritime Stations... Kihei 68 MPH 0832 PM 12/05 Molokini Light 55 MPH 0934 PM 12/05 Kealakomo 34 MPH 0144 PM 12/05 Kawaihae (NOS-NWLON) 33 MPH 0924 PM 12/05 Honolulu, HI (NOS-NWLON) 28 MPH 0230 AM 12/06
Observations are collected from a variety of sources with varying equipment and exposures. We thank all volunteer weather observers for their dedication. Not all data listed are considered official.
Follow us on Twitter
Follow us on Facebook
Follow us on YouTube
HFO RSS Feed