Alert archive / Hawaii / Flash Flood Warnings in 2004

Flash Flood Warning 60, NWS Honolulu, HI

August 4, 2004Kauai County, Hawaii

NWS Honolulu, HI issued this flash flood warning at Aug 4, 2004, 10:45 AM HST for Kauai County, Hawaii. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 4, 2004, 10:45 AM HST (20:45 UTC)
Expired: Aug 4, 2004, 1:45 PM HST
In force: 3 hr
Issued by: NWS Honolulu, HI
Area: Counties, with a storm outline in the text

County Kauai County, HI

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this flash flood warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Lihue, (PHLI), launched 12:00Z, 8.8 hours before the alert went out and 17 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1527 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 476 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: 43 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 1.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGHW50 PHFO 042045
FFWHFO
HIC007-042345-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HONOLULU HI
1045 AM HST WED AUG 4 2004

THE NATIONAL WEATHER SERVICE IN HONOLULU HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  THE ISLAND OF KAUAI IN KAUAI COUNTY

* UNTIL 145 PM HST

* AT 1045 AM HST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A LINE OF HEAVY SHOWERS MOVING ACROSS THE SOUTHEASTERN PORTION OF 
  THE ISLAND AFFECTING AREAS FROM KAPAA TO HANAPEPE. HEAVY SHOWERS 
  WILL DEVELOP OVER THE ENTIRE ISLAND DURING THE NEXT COUPLE OF 
  HOURS AND PERSIST INTO TONIGHT.

* LOCATIONS IMPACTED INCLUDE...
  ALL LOCATIONS ON KAUAI.

MOTORISTS SHOULD BE ALERT FOR FLOODING AND SHOULD NOT ATTEMPT TO
CROSS FAST FLOWING OR RISING WATER...MANY FLASH FLOOD DEATHS OCCUR
WHEN MOTORISTS TRY CROSSING FLOODED ROADWAYS. TURN AROUND...DON/T
DROWN

ESCAPE RISING WATER BY CLIMBING DIRECTLY TO HIGHER GROUND. NEVER TRY
TO OUTRACE A FLOOD...EITHER ON FOOT OR IN YOUR VEHICLE. DO NOT CAMP
NEAR STREAMS OR OTHER AREAS SUBJECT TO FLOODING.

STAY TUNED TO NOAA WEATHER RADIO OR OTHER LOCAL MEDIA SOURCES FOR THE
LATEST SEVERE WEATHER INFORMATION. REPORT FLOODING TO THE POLICE FOR
IMMEDIATE RELAY TO THE NATIONAL WEATHER SERVICE.

LAT...LON 2180 15952 2204 15922 2234 15934 2210 15993

$$
WROE

What forecasters said that day

The local office's own words before this flash flood warning went out, 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 this flash flood warning went out at Aug 4, 10:00 AM HST, 45 minutes earlier.

Area forecast discussion, Aug 4, 10:00 AM HST, 45 minutes before

HAWAIIAN ISLANDS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST WED AUG 4 2004

.SYNOPSIS...
TROPICAL MOISTURE FROM THE REMNANTS OF HURRICANE DARBY REMAINS OVER
THE WESTERN PORTION OF THE MAIN HAWAIIAN ISLANDS THIS MORNING. HEAVY
SHOWERS AND THUNDERSTORMS WILL CONTINUE OVER THE ISLANDS WEST OF
MAUI...WITH CONDITIONS CLEARING SLOWLY FROM THE EAST TO WEST.
MOLOKAI AND OAHU WILL CLEAR LATER TODAY...THOUGH HEAVY SHOWERS AND
THUNDERSTORMS WILL DEVELOP OVER KAUAI BEFORE MIDDAY AND CONTINUE
TONIGHT. TRADE WINDS...WITH THEIR MORE NORMAL PATTERN OF WINDWARD
AND MAUKA...NIGHT AND MORNING SHOWERS...WILL RETURN ON THURSDAY.

&&

.DISCUSSION...
WIDESPREAD RAIN WITH EMBEDDED HEAVY SHOWERS CONTINUES OVER THE
ISLAND OF OAHU THIS MORNING...WHILE MOST SHOWER ACTIVITY HAS CLEARED
THE BIG ISLAND AND MAUI COUNTY. THE HEAVY RAINFALL WAS DELIVERED BY
THE REMNANTS OF FORMER HURRICANE DARBY...NOW A SURFACE TROUGH
LOCATED JUST WEST OF OAHU IN THE KAUAI CHANNEL. AMPLE LOW LEVEL
MOISTURE FROM THIS SYSTEM IS PASSING UNDER AN UPPER LEVEL TROUGH
CENTERED JUST WEST OF THE STATE. THE RESULT IS A VERY FAVORABLE
ENVIRONMENT FOR WIDESPREAD RAIN...HEAVY SHOWERS...AND THUNDERSTORMS.
AS OF 930 AM HST...OAHU REMAINS UNDER THE HIGHEST CONVERGENCE OF THE
LOW LEVEL MOISTURE...WITH THE EASTERN EDGE OF THE CLOUDS AND RAIN
OVER WESTERN MOLOKAI. THE SURFACE TROUGH IS MOVING TO THE WEST
SLOWLY AND WILL CLEAR OAHU BY LATE THIS AFTERNOON.

WITH THE WESTWARD MOVEMENT OF THE SURFACE TROUGH...KAUAI WILL BE
THE NEXT ISLAND TO RECEIVE WIDESPREAD RAIN WITH HEAVY SHOWERS. THESE
CONDITIONS WILL DEVELOP IN THE NEXT COUPLE OF HOURS. HEAVY SHOWERS
AND ISOLATED THUNDERSTORMS WILL CONTINUE ON KAUAI INTO THE NIGHT
WITH CLEARING EXPECTED IN THE EARLY MORNING HOURS.

BY THURSDAY AND FRIDAY MORE TYPICAL TRADE WIND WEATHER IS EXPECTED
THANKS TO HIGH PRESSURE FAR NORTH OF THE STATE. TRADE WINDS WILL BE
IN THE 10 TO 20 MPH RANGE WITH SHOWERS MAINLY CONFINED TO WINDWARD
AND MAUKA AREAS.

&&

.LONG TERM...
WE ARE ALSO WATCHING ANOTHER DECAYING TROPICAL SYSTEM THAT MAY
APPROACH THE ISLANDS OVER THE WEEKEND. THE REMNANTS OF TROPICAL
DEPRESSION SIX-E ARE LOCATED ABOUT 1150 MILES EAST SOUTHEAST OF
HILO. THE GFS MODEL BRINGS A LARGE AREA OF REMNANT TROPICAL MOISTURE
OVER THE STATE LATE FRIDAY THROUGH EARLY SUNDAY...PROVIDING A
THREAT OF HEAVY RAINFALL ONCE AGAIN TO THE STATE.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH KAUAI OAHU AND MOLOKAI.

&&

WROE

The office that day

Everything else NWS Honolulu, HI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 3, 2:20 PM HST	Flash Flood Warning	HFO	Kalawao	3 hr
Aug 3, 7:11 PM HST	Flash Flood Warning	HFO	Kalawao	3 hr
Aug 4, 3:45 AM HST	Flash Flood Warning	HFO	Honolulu	3 hr
Aug 4, 6:45 AM HST	Flash Flood Warning	HFO	Honolulu	3 hr
Aug 4, 9:32 AM HST	Flash Flood Warning	HFO	Honolulu	3 hr

Nearby

Flash Flood Warnings in Hawaii, 2004 Every flash flood warning in 2004

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.