Public Information Statement...UPDATED
National Weather Service Honolulu HI
408 PM HST Mon Apr 16 2018

...RECORD-BREAKING RAINFALL PRODUCES SEVERE FLOODING OVER THE 
WEEKEND...

...KUHIO HIGHWAY NEAR THE HANALEI BRIDGE REMAINS CLOSED TO THE
PUBLIC...

EVENT SUMMARY... An upper level low pressure system which tapped 
into enhanced moisture in the lower levels of the atmosphere 
produced torrential rainfall and severe flooding over portions of 
the state from late Friday, April 13, through Sunday, April 15. 
Impacts on April 13 were mainly over east Oahu as a result of a
strong thunderstorm which affected the area from 7 PM to 9 PM HST.
Severe localized flooding affected communities from Maunawili to 
Waimanalo over the windward slopes, and from Aina Haina to Hawaii
Kai along the leeward slopes. 

Kauai suffered the worst impacts in the state from the storm 
event. Heavy rainfall started late Saturday, April 14 and 
continued through the evening of April 15. Communities west of 
Princeville were cut off from the rest of the island. Severe 
flooding also occurred over the east and south sides of the island
during different phases of the event. The windward slopes of the 
Big Island had periods of heavy rainfall during the weekend. A few
roads were closed by flooding in the South Hilo and Puna 
Districts early Sunday morning.

Please refer to the Local Storm Report Summary for more specifics
on individual reports throughout the event at: 

www.prh.noaa.gov/hnl/pages/lsr.php

Here are significant rainfall totals from Kauai, Oahu, and the Big
Island during the 48-hour period ending at 6 PM HST on April 15, 
2018. All values are in inches.

Kauai
Wainiha               : 32.35
Hanalei               : 28.41
Mount Waialeale       : 22.34
Princeville Airport   : 14.60
Kilohana              : 13.19
North Wailua Ditch    : 10.62
Kapahi                : 10.12
Wailua                :  8.21
Lihue Variety Station :  3.36
Anahola               :  3.20 
Lihue Airport         :  1.92 
Kalaheo               :  1.55

Oahu
Manoa Lyon Arboretum  : 11.96
Nuuanu Upper          :  7.88
Niu Valley            :  5.64
Maunawili             :  5.58
Waimanalo             :  5.02
Olomana Fire Station  :  4.70
Kamehame              :  3.53
St. Stephens          :  3.46
Bellows               :  3.21

Big Island
Pahoa                 :  5.60
Mountain View         :  5.51
Saddle Road Quarry    :  5.21
Waiakea Uka           :  4.50
Piihonua              :  4.25
Waiakea Exp. Station  :  3.88
Hilo Airport          :  3.05
Glenwood              :  3.01
Papaikou Well         :  2.30

In addition to the automated site totals, a volunteer observer
with the Community Collaborative Rain, Hail, and Snow Network, or
CoCoRaHS, reported 36.49 inches at Wainiha during the 24-hour 
period ending at 7 AM HST on April 15.

The peak 24-hour rainfall at Hanalei was 28.15 inches as of 2 AM 
HST when the gage stopped reporting. The record 24-hour rainfall 
at this site is 28.54 inches for the period from 4 AM HST March 4,
2012 to 4 AM HST March 5, 2012. While the current event total was
slightly less than the record, it is highly likely that this 
record was broken by heavy rainfall after the gage stopped 
reporting.

The Wainiha total of 19.54 inches for the 24-hour period ending at
4 PM HST is a record for this site, breaking the previous long 
term record of 16.70 inches from January 6, 1969.

$$

Kodama/Gibbs/Jelsema