Hawaii, 2023

Debris Flows and Flooding in Hawaii, November 30, 2023

November 30, 2023 · NWS HFO · 6 events in 3 counties and zones

A kona low developed west-northwest of the Hawaiian Islands and brought periods of heavy rainfall and isolated thunderstorms. Heavy rainfall lead to localized flash flooding and landslides across portions of the State.

Where it happened

Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. 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
6

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.

A kona low developed west-northwest of the Hawaiian Islands and brought periods of heavy rainfall and isolated thunderstorms. Heavy rainfall lead to localized flash flooding and landslides across portions of the State. Impacts from the kona low continued into December 2023 and are covered in episode 186869.

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 Nov 29, 8:51 PM HST, 6 hours 9 minutes earlier.

Area forecast discussion, Nov 29, 8:51 PM HST, 6 hours 9 minutes before
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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

2 debris flow, 2 high wind, 2 flood. Local standard time, as filed.

Debris Flow, Hawaii

When
November 30, 3:00 AM HST to 9:00 AM HST
Where
Hawaii County, 1.16 mi SE of Hakalau to 0.96 mi SE of Hakalau
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
19.888, -155.117

The Hawaii Police Department reported a landslide closing the Hawaii Belt Rd (Highway 19) between Mile Marker Twelve and Honomu Rd.

Debris Flow, Hawaii

When
November 30, 3:00 AM HST to 9:00 AM HST
Where
Hawaii County, 0.67 mi W of Paauilo to 1.25 mi SE of Paauilo
Cause
Heavy Rain
Reported by
Emergency Manager
Coordinates
20.051, -155.380

A landslide was reported near Mile Marker 28 in Kawaili Gulch along Hawaii Belt rd. (Highway 19).

High Wind, Big Island Southeast

When
November 30, 3:00 PM HST to 4:00 PM HST
Where
Big Island Southeast forecast zone
Measured
66 kt (76 mph) estimated gust
Reported by
Mesonet
Coordinates
19.602, -155.523 (the zone’s center; the record gives no point)

Flood, Hawaii

When
November 30, 3:28 PM HST to 11:05 PM HST
Where
Hawaii County, 4.41 mi N of Pahala to 4.54 mi N of Pahala
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
19.264, -155.476

Persistent heavy rainfall lead to water accumulating on the roads which prompted the road closure of Wood Valley Road.

Flood, Maui

When
November 30, 4:37 PM HST to 11:59 PM HST
Where
Maui County, 0.13 mi W of Koali to 0.16 mi NNE of Kipahulu
Cause
Heavy Rain
Reported by
Law Enforcement
Coordinates
20.680, -156.032

Periods of heavy rainfall lead to an accumulation of water on the roadways which led to the closure of Piilani highway from mile marker 29-31, as well as mile marker 16. Hana Highway was also closed near mile marker 40.

High Wind, Big Island Southeast

When
November 30, 5:00 PM HST to 6:00 PM HST
Where
Big Island Southeast forecast zone
Measured
61 kt (70 mph) estimated gust
Reported by
Park/Forest Service
Coordinates
19.602, -155.523 (the zone’s center; the record gives no point)

What these are

Debris Flow
A fast-moving slurry of mud, rock and debris, usually on a slope soaked by heavy rain or stripped by a fire.
High Wind
Sustained non-thunderstorm winds of 40 mph or more for an hour, or gusts of 58 mph or more.
Flood
Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

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

The same day elsewhere

More

Every storm in Hawaii in 2023Every state in 2023This day in weather historyWarnings in Hawaii, November 2023

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: 1144654, 1144655, 1144649, 1143752, 1143753, 1144650.