A slow-moving surface trough, heading east to west, and an upper disturbance triggered heavy showers and isolated thunderstorms that caused flash flooding in some instances.  Damages occurred to public and private property, including roads and bridges washed out. Nine homes were destroyed, 44 suffered major damage, and 55 suffered minor damage.  No significant injuries were reported.

Heavy Rain in KAUAI, HAWAII
From 06-MAR-21 06:35:00 to 06-MAR-21 17:23:00 (HST-10)
Location: NA PALI COAST SP
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Debris Flow in KAUAI, HAWAII
From 06-MAR-21 10:55:00 to 06-MAR-21 10:55:00 (HST-10)
Location: HANALEI
Flood cause: Heavy Rain
Property damage: 3.90M
Crop damage: 0.00K
Reported by: Department of Highways

Rocks and soil caused the closure of one lane of Kuhio Highway at mile marker 4.5, near Waikoko on Kauai's north shore.

Heavy Rain in HAWAII, HAWAII
From 07-MAR-21 17:22:00 to 07-MAR-21 23:15:00 (HST-10)
Location: PAPAALOA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in MAUI, HAWAII
From 08-MAR-21 10:04:00 to 08-MAR-21 14:20:00 (HST-10)
Location: PUUKOLII
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Flash Flood in MAUI, HAWAII
From 08-MAR-21 16:35:00 to 08-MAR-21 18:15:00 (HST-10)
Location: HAIKU
Flood cause: Heavy Rain
Property damage: 14.30M
Crop damage: 0.00K
Reported by: Emergency Manager

Hana Highway was closed from Peahi Road near Haiku to Keanae in windward East Maui due to flooding.  A dam failure in the same area was a possibility as water topped the Kaupakulua Dam upstream from the Haiku and Pauwela communities.  The dam survived the downpours, however.

Heavy Rain in HAWAII, HAWAII
From 08-MAR-21 13:09:00 to 09-MAR-21 01:10:00 (HST-10)
Location: OOKALA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in MAUI, HAWAII
From 08-MAR-21 21:32:00 to 09-MAR-21 03:25:00 (HST-10)
Location: HAIKU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in KAUAI, HAWAII
From 08-MAR-21 22:55:00 to 09-MAR-21 04:55:00 (HST-10)
Location: KAUNALEWA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in HONOLULU, HAWAII
From 09-MAR-21 05:02:00 to 09-MAR-21 08:33:00 (HST-10)
Location: KAWAILOA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Flash Flood in HONOLULU, HAWAII
From 09-MAR-21 10:35:00 to 10-MAR-21 00:00:00 (HST-10)
Location: KANEOHE
Flood cause: Heavy Rain
Property damage: 2.70M
Crop damage: 1.80M
Reported by: County Official

Four feet of water from heavy rain flooded William Henry Road in Kaneohe in windward Oahu.  A blocked drain caused the backup of water, inundating some homes in the area.  Major flooding problems continued over windward portions of Oahu and the North Shore, especially around Haleiwa and Waialua. The Opaeula Stream overflowed at Haleiwa Road and caused flooding of homes in the area.  Also in windward Oahu, flooding was reported along Okana Road and a partial road closure occurred on Kamehameha Highway between Wailehua Road and Waikane Store.

Heavy Rain in HAWAII, HAWAII
From 09-MAR-21 10:55:00 to 09-MAR-21 21:26:00 (HST-10)
Location: AKAKA FALLS ST PARK
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in KAUAI, HAWAII
From 09-MAR-21 15:47:00 to 09-MAR-21 16:30:00 (HST-10)
Location: KOKEE STATE PARK
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Debris Flow in HONOLULU, HAWAII
From 09-MAR-21 11:05:00 to 09-MAR-21 11:05:00 (HST-10)
Location: MAUNAWILI
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: County Official

A small section of the Pali Highway, in the Kaneohe-bound lane, was blocked by debris from the nearby steep terrain.

Debris Flow in MAUI, HAWAII
From 09-MAR-21 11:20:00 to 09-MAR-21 11:20:00 (HST-10)
Location: KEANAE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Hana Highway was closed between mile post 10 and mile post 13, about 2 miles west-northwest of Keanae in windward East Maui.  The closure was caused by large boulders blocking the roadway.

Flash Flood in KAUAI, HAWAII
From 09-MAR-21 17:26:00 to 10-MAR-21 09:11:00 (HST-10)
Location: PRINCEVILLE
Flood cause: Heavy Rain
Property damage: 30.10M
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rain caused the Hanalei River to overflow near the Hanalei Bridge, which then closed Kuhio Highway in that area.  Other areas in northern Kauai were affected by downpours that caused debris flows unto roadways, near Princeville, Kilauea, and Wailoko.  Other areas that had problems were near Lihue at Niumalu and Hulemalu roads, and in Kapaa where the Keapana Bridge became impassable.

Heavy Rain in MAUI, HAWAII
From 09-MAR-21 22:56:00 to 10-MAR-21 01:54:00 (HST-10)
Location: WAILUA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in HAWAII, HAWAII
From 10-MAR-21 01:02:00 to 10-MAR-21 11:01:00 (HST-10)
Location: HILO
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Debris Flow in HAWAII, HAWAII
From 09-MAR-21 18:17:00 to 09-MAR-21 18:17:00 (HST-10)
Location: HAKALAU
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

One lane of Highway 19 in windward Big Island near Hakalau, and the Hakalau Bridge, was closed due to debris on the roadway.

Heavy Rain in KAUAI, HAWAII
From 10-MAR-21 09:11:00 to 10-MAR-21 21:21:00 (HST-10)
Location: KOKEE STATE PARK
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in HONOLULU, HAWAII
From 10-MAR-21 13:09:00 to 10-MAR-21 13:45:00 (HST-10)
Location: KAWAILOA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Flash Flood in HONOLULU, HAWAII
From 10-MAR-21 15:45:00 to 10-MAR-21 22:52:00 (HST-10)
Location: WAIKANE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Kamehameha Highway in windward Oahu was closed at the Waikane Bridge due to flooding.  More flooding conditions occurred around Oahu - along Kamehameha Highway near Kualoa Point (and Kualoa Ranch), and in Waikiki at Hobron Lane where cars stalled due to high water there.

Heavy Rain in MAUI, HAWAII
From 10-MAR-21 15:45:00 to 10-MAR-21 18:36:00 (HST-10)
Location: KEAWAKAPU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in HAWAII, HAWAII
From 10-MAR-21 16:30:00 to 10-MAR-21 18:37:00 (HST-10)
Location: GLENWOOD
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Debris Flow in HONOLULU, HAWAII
From 10-MAR-21 18:20:00 to 10-MAR-21 18:20:00 (HST-10)
Location: WAIMEA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

There was a partial closure of Kamehameha Highway near Waimea Bay on Oahu's North Shore as a large boulder blocked traffic for a time.

Heavy Rain in HONOLULU, HAWAII
From 11-MAR-21 02:23:00 to 11-MAR-21 09:26:00 (HST-10)
Location: BARBERS PT HOUSING
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in KAUAI, HAWAII
From 11-MAR-21 03:21:00 to 11-MAR-21 11:53:00 (HST-10)
Location: KAUNALEWA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Lightning in HONOLULU, HAWAII
From 10-MAR-21 18:34:00 to 10-MAR-21 22:30:00 (HST-10)
Location: MOILILI
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Lightning strikes on Oahu led to power outages from Honolulu to Hauula.  Power was restored after several hours for most locales as lines were repaired.