Alert archive / Hawaii / Flash Flood Warnings in 2004

Flash Flood Warning 72, NWS Honolulu, HI

December 26, 2004Honolulu County, Hawaii

NWS Honolulu, HI issued this flash flood warning at Dec 26, 2004, 11:34 PM HST for Honolulu 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
Dec 26, 2004, 11:34 PM HST (09:34 UTC)
Expired
Dec 27, 2004, 2:30 AM HST
In force
3 hr
Issued by
NWS Honolulu, HI
Area
Counties, with a storm outline in the text

County Honolulu 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 00:00Z, 9.6 hours before the alert went out and 145 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-pSkew-T log-p diagram, Lihue, at 00:00Z on 2004-12-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 433 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lihue, at 00:00Z on 2004-12-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
433 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
859 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
62 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

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

000
WGHW50 PHFO 270934
FFWHFO
HIC003-271230-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HONOLULU HI
1134 PM HST SUN DEC 26 2004

THE NATIONAL WEATHER SERVICE IN HONOLULU HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  THE ISLAND OF OAHU IN HONOLULU COUNTY

* UNTIL 230 AM HST

* AT 1134 PM HST...RADAR INDICATED THUNDERSTORMS WITH VERY HEAVY 
  RAINFALL OVER SOUTHWESTERN OAHU. THE THUNDERSTORMS WERE MOVING 
  NORTH AT 15 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  WAIANAE...KAPOLEI...MAKAKILO...MILILANI...WHEELER AFB...  
  SCHOFIELD BARRACKS...WAHIAWA...EWA BEACH...AND WHITMORE VILLAGE.

THIS FLASH FLOOD WARNING REPLACES THE URBAN AND SMALL STREAM FLOOD 
ADVISORY THAT WAS IN EFFECT.

NEVER DRIVE INTO AREAS WHERE WATER COVERS THE ROAD. IT ONLY TAKES A 
FEW INCHES OF WATER TO FLOAT MOST VEHICLES.

LAT...LON 2124 15817 2124 15798 2159 15802 2148 15825

$$
R BALLARD
2 follow-up statements
000
WGHW70 PHFO 271123
FFSHFO

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE HONOLULU HI
125 AM HST MON DEC 27 2004

HIC003-271230-
HONOLULU-
125 AM HST MON DEC 27 2004

...A FLASH FLOOD WARNING CONTINUES UNTIL 230 AM HST FOR THE ISLAND OF
OAHU IN HONOLULU COUNTY...

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO NANAKULI...
WAIPIO...MAILI...WAIANAE...MILILANI TOWN...WHEELER AFB...SCHOFIELD
BARRACKS...WAHIAWA AND WHITMORE VILLAGE.

LAW ENFORCEMENT OFFICIALS REPORTED ELEVATED STREAM LEVELS AT KIPAPA  
GULCH AND WAIKAKALAUA STREAM BUT NO ROAD CLOSURES OR FLOODING.  

RADAR DATA INDICATED THAT THE HEAVIEST RAINFALL HAS MOVED OFF OAHU 
TOWARD THE NORTH.  HOWEVER...ANOTHER BAND OF HEAVY RAINS IS 
DEVELOPING WEST OF OAHU AND STREAM LEVELS OVER CENTRAL AND WEST OAHU 
REMAIN ELEVATED.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODS AND FLASH FLOODS.

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.

LAT...LON 2124 15817 2124 15798 2159 15802 2148 15825

$$

KODAMA
000
WGHW70 PHFO 271219
FFSHFO

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE HONOLULU HI
220 AM HST MON DEC 27 2004

HIC003-271235-
HONOLULU-
220 AM HST MON DEC 27 2004

...THE FLASH FLOOD WARNING FOR THE ISLAND OF OAHU IN
HONOLULU COUNTY IS CANCELLED...

HEAVY RAIN HAS ENDED AND FLASH FLOODING IS NO LONGER EXPECTED.  LAW 
ENFORCEMENT REPORTED NO SERIOUS FLOODING PROBLEMS AND ONLY LOCALIZED 
AREAS OF ROAD PONDING.

LAT...LON 2124 15817 2124 15798 2159 15802 2148 15825

$$

KODAMA

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 Dec 26, 9:08 PM HST, 2 hours 26 minutes earlier.

Area forecast discussion, Dec 26, 9:08 PM HST, 2 hours 26 minutes before
HAWAIIAN ISLANDS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
908 PM HST SUN DEC 26 2004

SYNOPSIS...
A SLOW MOVING COLD FRONT WILL BRING WET WEATHER TO MAINLY THE
SMALLER ISLANDS TONIGHT AND MONDAY. LINGERING MOISTURE OVER THE
STATE...AND AN UPPER TROUGH TO OUR WEST...MAY KEEP THE WEATHER
SOMEWAT UNSETTLED THROUGH MUCH OF THE WEEK. A STRONG COLD FRONT MAY
BRING GUSTY KONA WINDS AND POSSIBLY STORMY WEATHER BY NEW YEARS EVE.

&&

.UPDATE...
HAVE UPDATED THE GRIDS TO PLACE THUNDERSTORMS IN THE FORECAST FOR
OAHU AND PORTIONS OF MAUI COUNTY AS WELL. VIGOROUS SHORTWAVE
ROTATING AROUND THE BASE OF THE UPPER TROUGH...ACCOMPANIED BY A 110
MILE WIDE BAND OF SHOWERS AND THUNDERSTORMS THAT IS PUSHING STEADILY
EASTWARD. REMAINDER OF THE FORECAST IS UNCHANGED AND THE PREVIOUS
DISCUSSION FROM 4 PM FOLLOWS.

&&

.PREV DISCUSSION...
THE GFS MODEL RUN KEEPS SHOWERS OVER KAUAI AND OAHU THROUGH
MONDAY...AND SPREADS THEM TO THE OTHER ISLANDS TUESDAY AND
WEDNESDAY. ANOTHER FRONT BRINGS IN MORE WIDESPREAD SHOWERS THURSDAY
AND FRIDAY...ALONG WITH ENOUGH INSTABILITY TO ASSURE THE BIG ISLAND
OF SOME THUNDERSTORMS AS WELL.

AT THE MOMENT...SATELLITE IMAGERY A BAND OF HEAVY SHOWERS AND
THUNDERSTORMS ALONG 160W. THIS BAND MARKS THE LEADING EDGE OF A COLD
FRONT NORTH OF 20N...WITH CONVERGENCE OF TROPICAL MOISTURE SOUTH OF
20N. OTHER AREAS OF SCATTERED SHOWERS CAN BE SEEN OVER THE WATERS
AROUND THE ISLANDS. THE SHOWERS AND THUNDERSTORMS OVER AND AROUND
KAUAI WILL MOVE EAST TONIGHT...TO OAHU AT LEAST.

A BROAD SURFACE RIDGE LIES OVER THE CENTRAL ISLANDS AND IS
RESPONSIBLE FOR KEEPING GENERALLY EASTERLY TO SOUTHEAST WINDS OVER
THE BIG ISLANDS...AND SOUTHEAST WINDS OVER THE STATE FROM MAUI TO
OAHU. THE FRONT WEST OF KAUAI HAS TURNED WINDS THERE MORE SOUTHERLY.
COMPUTER FORECAST MODELS BRING THIS FRONT TO KAUAI TONIGHT...THEN
WEAKEN IT INTO A SURFACE TROUGH OVER THE WESTERN ISLANDS MONDAY AND
TUESDAY. THUS AT LEAST THE ISLANDS OF KAUAI AND OAHU ARE IN STORE
FOR SHOWERS...WITH CHANCE FOR A THUNDERSTORM AROUND KAUAI...THROUGH
MONDAY. THESE MODELS ALSO BRING TROPICAL MOISTURE FROM SOUTH OF THE
STATE UP OVER THE ISLANDS TUESDAY AND WEDNESDAY...THUS THE CHANCE
FOR SHOWERS EXISTS ON ALL ISLANDS THROUGH MIDWEEK.

THE NEXT LOW PRESSURE SYSTEM AND ITS ASSOCIATED FRONT IS FORECAST TO
MAKE ITS PRESENCE KNOWN TO THE ISLANDS AS EARLY AS LATE WEDNESDAY BY
TURNING WINDS SOUTHERLY STATEWIDE. THESE WINDS WILL INCREASE
SIGNIFICANTLY AHEAD OF THIS COLD FRONT THURSDAY NIGHT AND FRIDAY...
INTRODUCING THE LIKELIHOOD OF WIND ADVISORIES FOR THE NORMALLY
WINDWARD SIDES OF THE ISLANDS...AND HIGH WIND WARNINGS FOR THE BIG
ISLAND SUMMITS. THIS SYSTEM WILL ALSO BRING A MORE SIGNIFICANT
POTENTIAL FOR HEAVY SHOWERS AND THUNDERSTORMS...ESPECIALLY NEAR THE
BIG ISLAND...AS IT BRINGS INSTABILITY TO THE STATE NEW YEARS EVE.
ANOTHER POWERFUL SYSTEM BEHIND THIS ONE WILL CONTINUE THE WINDS AND
WET WEATHER ON NEW YEARS DAY...WITH AN UNUSUAL BOUT OF BRISK
WESTERLY WINDS CONTINUING THROUGH THE END OF THE FORECAST PERIOD.

&&

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

&&

R BALLARD

In the hours before

Local storm report, Dec 26, 10:27 PM HST, 1 hour 7 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HONOLULU HI
1027 PM HST SUN DEC 26 2004

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0900 PM     HEAVY RAIN       EWA BEACH               21.32N 158.01W
12/26/2004  0.40 INCH        HONOLULU           HI   TRAINED SPOTTER

            0.40 OF RAIN IN TEN MINTUES

1015 PM     HEAVY RAIN       KANEOHE                 21.41N 157.79W
12/26/2004  0.30 INCH        HONOLULU           HI   TRAINED SPOTTER

            0.30 INCH OF RAIN IN 25 MINUTES

&&

RAB

Nearby

Flash Flood Warnings in Hawaii, 2004Every 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.