Hawaii, 2016

Flash Flood and Heavy Rain in Hawaii, October 3 to 6, 2016

October 3 to 6, 2016 · NWS HFO · 7 events in 3 counties and zones

The combination of upper-level instability and tropical moisture, some of which were remnants from former Tropical Storm Ulika, generated heavy rain and isolated thunderstorms over the parts of the Big Island of Hawaii, Maui, and Oahu. The precipitation produced small stream and drainage ditch flooding, and ponding on roadways.

Where it happened

Every event with a place to put it. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
7

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS HFO wrote it up.

The combination of upper-level instability and tropical moisture, some of which were remnants from former Tropical Storm Ulika, generated heavy rain and isolated thunderstorms over the parts of the Big Island of Hawaii, Maui, and Oahu. The precipitation produced small stream and drainage ditch flooding, and ponding on roadways. However, on the Big Island in the evening of the 4th and the morning of the 5th, the almost non-stop rain caused some areas around Hilo Bay to be submerged under 2 feet of water. No serious injuries or property damage were reported.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Honolulu, HI wrote its last area forecast discussion before the first event at Oct 3, 9:57 AM HST, 4 hours 13 minutes earlier.

Area forecast discussion, Oct 3, 9:57 AM HST, 4 hours 13 minutes before
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The radar

The Kamuela/Kohala Apt radar (PHKM), 16 km away, was scanning. The volume nearest the first event began at 00:13 UTC.

Open the radar archive at this moment

Event by event

6 heavy rain, 1 flash flood. Local standard time, as filed.

Heavy Rain, Hawaii

When
October 3, 2:10 PM HST to 4:54 PM HST
Where
Hawaii County, 0.66 mi SW of Kamuela to 0.66 mi ESE of Kailua Kona
Reported by
Official NWS Observations
Coordinates
20.023, -155.676

Heavy Rain, Maui

When
October 3, 6:21 PM HST to October 4, 2:30 AM HST
Where
Maui County, 1.56 mi SW of Haiku to 1.51 mi WSW of Koali
Reported by
Official NWS Observations
Coordinates
20.903, -156.335

Heavy Rain, Honolulu

When
October 4, 6:58 AM HST to 9:50 AM HST
Where
Honolulu County, 0.9 mi SE of Waimalu to 0.64 mi NNW of Waimanalo Beach
Reported by
Official NWS Observations
Coordinates
21.389, -157.942

Flash Flood, Hawaii

When
October 4, 4:41 PM HST to 5:03 PM HST
Where
Hawaii County, 1.05 mi WSW of Waikoloa Village to 1.14 mi WSW of Waikoloa Village
Cause
Heavy Rain
Reported by
County Official
Coordinates
19.926, -155.796

A ditch overflowed in Waikoloa causing flooding at Pua Melia Street and Waikoloa Road.

Heavy Rain, Maui

When
October 4, 5:33 PM HST to October 5, 8:08 AM HST
Where
Maui County, 1.7 mi WSW of Keanae to 0.84 mi NE of Kipahulu
Reported by
Official NWS Observations
Coordinates
20.860, -156.174

Heavy Rain, Hawaii

When
October 4, 8:16 PM HST to October 5, 10:28 AM HST
Where
Hawaii County, 1.43 mi S of Ookala to 0.92 mi SSE of Glenwood
Reported by
Official NWS Observations
Coordinates
19.999, -155.281

Heavy Rain, Hawaii

When
October 6, 6:33 PM HST to 8:03 PM HST
Where
Hawaii County, 1.04 mi WNW of Papa to 7.09 mi SE of Hawaiian Ocean Vw Est
Reported by
Official NWS Observations
Coordinates
19.206, -155.885

What these are

Heavy Rain
Rainfall totals unusual for the place and season that did not produce a flood.
Flash Flood
Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Hawaii in 2016Every state in 2016This day in weather historyWarnings in Hawaii, October 2016

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-30. Each event’s entry at NCEI: 659504, 659505, 659506, 660261, 659508, 659509, 659510.