Name: Heavy Rain in Hawaii, August 8, 2005
Start: 2005-08-08T12:05
End: 2005-08-08T18:00
Location: Hawaii

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

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Floods
Wind
Hail
Winter weather
Heat and drought
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The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

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.

Heavy showers and isolated thunderstorms caused ponding of roadways, and small stream and drainage ditch flooding in northern, windward, and leeward areas of the Big Island of Hawaii. There were reports that coffee plants were damaged in lee sections of the isle, in and around Kealakekua. However, no damage estimates were available. No significant injuries 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 Aug 8, 10:00 AM HST, 2 hours 5 minutes earlier.

Area forecast discussion, Aug 8, 10:00 AM HST, 2 hours 5 minutes before

HAWAIIAN ISLANDS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST MON AUG 8 2005

.SYNOPSIS...
MOISTURE ASSOCIATED WITH THE REMNANTS OF TROPICAL DEPRESSION ONE C
IN COMBINATION WITH A TROUGH ALOFT OVER HAWAII...HAS THE POTENTIAL
TO PRODUCE ISOLATED HEAVY SHOWERS AND THUNDERSTORMS OVER THE NEXT 18
TO 24 HOURS. THESE HEAVY SHOWERS AND THUNDERSTORMS WILL FAVOR THE
BIG ISLAND SLOPES THIS AFTERNOON AS SURFACE HEATING CONTRIBUTES TO
INSTABILITY. A BAND OF MOISTURE TRAILING BEHIND THE FORMER
DEPRESSION WILL INCREASE SHOWERS ACROSS THE ENTIRE REGION TONIGHT.

&&

.DISCUSSION...
WE ARE CAUTIOUSLY MONITORING THE REMNANTS OF TROPICAL DEPRESSION ONE
C...CURRENTLY CENTERED NEAR 17N 157.53W...OR ABOUT 175 MILES
SOUTHWEST OF SOUTH POINT ON THE BIG ISLAND AND MOVING TOWARD THE
WEST NEAR 20 MPH. THE REMNANT CIRCULATION CONTINUES TO SPAWN
THUNDERSTORMS NEAR THE CENTER...BUT ARE SUFFICIENTLY FAR AS TO NOT
IMPACT THE ISLANDS. HOWEVER...A BAND OF MOISTURE TRAILING AND
APPARENTLY ASSOCIATED WITH THE FORMER DEPRESSION IS CURRENTLY OVER
THE BIG ISLAND AND MAUI. THAT PORTION OF THE BAND EXTENDING
UPSTREAM OF THE STATE IS EXPECTED TO REACH THE SHORES OF THE
REMAINING ISLANDS THIS AFTERNOON AND OVERNIGHT.

AT UPPER LEVELS...A RELATIVELY SMALL BUT WELL DEFINED TROUGH IS
ALMOST DIRECTLY OVER THE HAWAIIAN ISLANDS. SOUNDINGS AND AIRCRAFT
DATA CONFIRM A FAIR AMOUNT OF INSTABILITY IN PLACE ACROSS THE
ISLANDS. SO...LOW LEVEL MOISTURE IN COMBINATION WITH UNSTABLE
CONDITIONS PRESENTS THE THREAT OF ISOLATED HEAVY SHOWERS AND/OR
THUNDERSTORMS...BUT MAINLY FOR THE BIG ISLAND...WHERE SURFACE
HEATING WILL PROVIDE AN EXTRA BOOST TO GET THINGS STARTED. BELIEVE
THAT THUNDERSTORM POTENTIAL FOR THE SMALLER ISLANDS IS QUITE
LOW...THOUGH A HEAVY SHOWER OR FEW ACROSS WINDWARD/MAUKA AREAS IS
CERTAINLY POSSIBLE.

IT WAS EARLIER ANTICIPATED THAT THE REMNANT CIRCULATION WOULD
INCREASE THE PRESSURE GRADIENT ACROSS THE STATE AND GIVE A BOOST TO
THE TRADES. HOWEVER...HIGH PRESSURE TO OUR NORTH WEAKENED A BIT MORE
THAN WAS EXPECTED...NEGATING THE PROJECTED INCREASE IN THE PRESSURE
GRADIENT. THE HIGH WILL REMAIN WEAK THROUGH THE FORECAST
PERIOD...KEEPING THE TRADES IN THE LIGHT TO MODERATE RANGE. OVER THE
SAME TIME FRAME...A TROUGH IN SOME FORM OR ANOTHER IS EXPECTED TO
REMAIN OVER THE STATE. ONCE THE REMNANTS OF TROPICAL DEPRESSION ONE
C AND THE ASSOCIATED BANDS OF MOISTURE CLEAR THE STATE SOMETIME
TOMORROW...THE CHANCE FOR HEAVY SHOWERS AND THUNDERSTORMS
DIMINISHES. AFTER THAT...THE UPPER TROUGH MAY NOT HAVE TOO MUCH OF
AN AFFECT ON ISLAND WEATHER.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

TANABE

The radar

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

Open the radar archive at this moment

Event by event

1 heavy rain. Local standard time, as filed.

Heavy Rain, Hawaii

When: August 8, 12:05 PM HST to 6:00 PM HST
Where: Hawaii County, Hawi
Reported by: OFFICIAL NWS OBS.
Coordinates: 19.602, -155.523 (the zone’s center; the record gives no point)

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 2005 Every state in 2005 This day in weather history Warnings in Hawaii, August 2005

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: 5469482.