Hawaii, 2020

Heavy Rain in Hawaii, April 1, 2020

April 1, 2020 · NWS HFO · 2 events in 2 counties and zones

With afternoon heating and sufficient low level moisture; heavy downpours, including isolated thunderstorms, formed over portions of the Big Island and Oahu. The rain caused 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
2

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.

With afternoon heating and sufficient low level moisture; heavy downpours, including isolated thunderstorms, formed over portions of the Big Island and Oahu. The rain caused small stream and drainage ditch flooding, and ponding on roadways. 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 Apr 1, 9:49 AM HST, 3 hours 31 minutes earlier.

Area forecast discussion, Apr 1, 9:49 AM HST, 3 hours 31 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 heavy rain. Local standard time, as filed.

Heavy Rain, Hawaii

When
April 1, 1:20 PM HST to 5:23 PM HST
Where
Hawaii County, 2.82 mi N of Waikoloa Village to 5.31 mi SW of Naalehu
Reported by
Official NWS Observations
Coordinates
19.971, -155.777

Heavy Rain, Honolulu

When
April 1, 1:38 PM HST to 3:11 PM HST
Where
Honolulu County, 0.62 mi E of Pomoho to 0.15 mi E of Honouliuli
Reported by
Official NWS Observations
Coordinates
21.521, -158.041

What these are

Heavy Rain
Rainfall totals unusual for the place and season that did not produce a flood.

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

The same day elsewhere

More

Every storm in Hawaii in 2020Every state in 2020This day in weather historyWarnings in Hawaii, April 2020

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 2026-09-24. Each event’s entry at NCEI: 879463, 879464.