Tornado, hail, and torrential rains hammer Hawaii

A waterspout made landfall on the Hawaiian island of Oahu Friday morning on the east shore town, becoming a rare Hawaiian tornado as it moved through the towns of Lanikai and Kailua. The twister, rated an EF-0 with winds of 60 - 70 mph, tore holes in roofs and downed trees along a 1 1/2 mile long, 20-yard wide path of damage. No injuries were reported. The same storm also brought golf ball sized hail raining down for about 45 minutes on Oahu. The islands have seen intense rains over the past week, thanks to a 1040 mb blocking high pressure system near 40°N, to the NNW of the island that forced a companion cutoff low near 25°N 165°W to stay put, bringing a series of heavy storms to the islands. Rainfall amounts over the past week have exceeded three feet in some locations. The resulting flooding forced the governor on Wednesday to declare two islands, Oahu and Kauai, disaster areas. The latest forecasts for Kauai and Oahu call for sporadic rains to continue over the weekend, followed by a drying trend during the coming week.


Video 1. On March 5, 2012, flooding rains of 3" per hour caused this creek to overflow the Loop Road on Kauai and wash away a pickup truck that tried to cross. The occupants evacuated safely.

Here are some select rainfall amounts over the past week, from the National Weather Service:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE HONOLULU HI
1155 AM HST FRI MAR 9 2012

...TORRENTIAL RAINS SLAM HAWAII IN THE PAST WEEK...

A SLOW MOVING FRONT BROUGHT HEAVY RAIN TO MOST ISLANDS THE PAST WEEK...AS IT INTERACTED WITH SEVERAL DISTURBANCES ALOFT. THE FOLLOWING REPRESENTS 7-DAY RAINFALL TOTALS...FROM 11 AM FRIDAY MARCH
2 THROUGH 11 AM FRIDAY MARCH 9.

KAUAI
HANALEI 45.97
WAINIHA POWER HOUSE 43.84
KAPAHI 32.66
MOUNT WAIALEALE RAINGAGE 31.32
LIHUE AIRPORT 13.59

OAHU
OAHU FOREST NWR 39.65
MOANALUA - USGS - USGS 36.42
PUNALUU STREAM - USGS 31.46
WILSON TUNNEL 25.05
LULUKU 22.25
PACIFIC TSUNAMI WARNING CENTER 20.47
HONOLULU AIRPORT 4.54

MOLOKAI
MOLOKAI AIRPORT 2.74

MAUI
PUU KUKUI - USGS 16.70
KAHULUI AIRPORT 2.34

HAWAII
HILO AIRPORT 5.97


Video 2. Damage from the March 9, 2012 tornado on Oahu.

Hawaii's tornado history
Tornadoes are rare in Hawaii. According to the Tornado History Project, only 39 tornadoes have hit the state since 1950, an average of one tornado every 1.5 years. The strongest tornadoes to hit the state occurred in 1982, when a series of three F-2 twisters struck Oahu in February and March. Those months are the most frequent months for tornadoes, with 44% of the total. No one has ever been killed in a Hawaiian tornado, but six people have been injured.

Jeff Masters