Alert archive / Hawaii / Flash Flood Warnings in 2004

Flash Flood Warning 70, NWS Honolulu, HI

November 22, 2004Hawaii County, Hawaii

NWS Honolulu, HI issued this flash flood warning at Nov 22, 2004, 10:02 PM HST for Hawaii 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
Nov 22, 2004, 10:02 PM HST (08:02 UTC)
Expired
Nov 23, 2004, 1:00 AM HST
In force
3 hr
Issued by
NWS Honolulu, HI
Area
Counties, with a storm outline in the text

County Hawaii 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

Hilo, (PITO), launched 00:00Z, 8.0 hours before the alert went out and 77 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, Hilo, at 00:00Z on 2004-11-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 448 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, Hilo, at 00:00Z on 2004-11-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 102 square meters per square second.1939Sfc1 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
448 J/kg
Mixed-layer CIN
-28 J/kg
Mixed-layer LCL
904 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
102 m²/s²
0-3 km storm-relative helicity
187 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.2

Open this sounding in Storm Lab

The text

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

000
WGHW50 PHFO 230806
FFWHFO
HIC001-231100-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE HONOLULU HI
1002 PM HST MON NOV 22 2004

THE NATIONAL WEATHER SERVICE IN HONOLULU HAS ISSUED A

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

* UNTIL 100 AM HST

* AT 954 PM HST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  VERY HEAVY RAIN FROM A STORM 6 MILES WEST OF PAHALA. THE STORM 
  PRODUCING HEAVY RAIN WAS NEARLY STATIONARY.

* LOCATIONS IMPACTED INCLUDE...
  PAHALA...NAALEHU...KAPAPALA...PUNALUU AND STREAMS ALONG HIGHWAY 11 
  ESPECIALLY NEAR KAWA FLATS.

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF STREAMS
AND COULD ALSO TRIGGER ROCK AND MUDSLIDES IN STEEP TERRAIN.

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 1921 15571 1896 15560 1929 15517 1949 15540

$$

KODAMA
1 follow-up statement
000
WGHW70 PHFO 231025
FFSHFO
HIC001-231032-

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE HONOLULU HI
1222 AM HST TUE NOV 23 2004

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

A FLASH FLOOD WATCH REMAINS IN EFFECT FOR THE ISLAND OF HAWAII 
THROUGH TUESDAY.

HEAVY RAINS OVER THE KAU AREA OF THE BIG ISLAND HAVE DIMINISHED.  
ALTHOUGH RADAR DATA INDICATED RAIN RATES AS HIGH AS 4 TO 6 INCH PER 
HOUR UPSLOPE OF PUNALUU AND HONUAPO...POLICE OFFICERS REPORTED NO 
FLOODING PROBLEMS.

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 1921 15571 1896 15560 1929 15517 1949 15540

$$

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 Nov 22, 8:30 PM HST, 1 hour 32 minutes earlier.

Area forecast discussion, Nov 22, 8:30 PM HST, 1 hour 32 minutes before
HAWAIIAN ISLANDS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
830 PM HST MON NOV 22 2004

.SYNOPSIS...
SURFACE TROUGHING WILL KEEP WINDS LIGHT AS AN UPPER LEVEL LOW
CONTINUES TO SLIDE SOUTHWARD ACROSS THE ISLANDS. COLD AIR ALOFT
ACCOMPANYING THIS UPPER LOW WILL DESTABILIZE THE ATMOSPHERE...
SETTING OFF HEAVY SHOWERS AND THUNDERSTORMS FROM THE BIG ISLAND
THROUGH OAHU...AND POSSIBLY KAUAI. THE HEAVIEST RAINFALL WILL
OCCUR ON THE BIG ISLAND OF HAWAII THROUGH TONIGHT...AS TROPICAL
MOISTURE IS ADDED INTO THE MIX THERE.

&&
.DISCUSSION...
HAVE JUST ISSUED A WINTER STROM WATCH FOR THE SUMMITS OF MAUNA KEA
AND MAUNA LOA ON THE BIG ISLAND DUE TO INCREASING DEEP CONVECTION IN
THE AREA. GRIDS AND ZONES WERE UPDATED TO INCLUDE THIS HEADLINE...
BUT NO OTHER CHANGES TO THE FORECAST WERE INCORPORATED AT THIS TIME.
HEAVY SHOWERS ARE AFFECTING WINDWARD BIG ISLAND...WITH THUNDERSTORMS
DEVELOPING NORTHEAST CLOCKWISE THROUGH SOUTHEAST OF THE ISLAND. THE
UPPER LOW IS BEHAVING AS EXPECTED...PROGRESSIVELY MOVING TOWARDS THE
SOUTH AT 10 TO 15 MPH...CURRENTLY CENTERED JUST NORTH OF MAUI. WHILE
MOST OF THE HEAVY RAIN IS CURRENTLY NEAR THE BIG ISLAND...SHOWERS
ARE INCREASING ALONG A WEAK BOUNDARY THAT EXTENDS NORTHWARD FROM
OAHU. DEVELOPING CONVECTION ALONG WINDWARD BIG ISLAND WILL RESULT IN
LOCALLY HEAVY DOWNPOURS. CELLS WILL BE MONITORED FOR POSSIBLE
TERRAIN ANCHORING...WHICH MAY RESULT IN LOCALIZED FLOODING. THE
RADAR AT SOUTH KOHALA/UPOLU POINT IS INCONVENIENTLY OUT OF
SERVICE...SO SATELLITE AND RAINGAGE DATA...AS WELL AS RADAR DATA
FROM SOUTH POINT...WILL BE UTILIZED TO DETERMINE THE EXTENT OF THE
HEAVY RAINFALL.

.PREV DISCUSSION...
AN UPPER LOW NEAR 24N 156W...ABOUT 215 MILES NORTHEAST OF
HONOLULU...AT 200 PM HAS BEEN MOVING SOUTH SOUTHWEST AROUND 15 MPH.
A WEAK SURFACE LOW HAS BEEN NOTED IN ASSOCIATION WITH THIS UPPER LOW
NEAR 25N 156W. THUNDERSTORMS ASSOCIATED WITH THIS SYSTEM HAVE BEEN
DRAWN NORTHWARD MAINLY TO THE EAST AND SOUTH OF THE BIG ISLAND OF
HAWAII. THIS UPPER LOW IF FORECAST TO CONTINUE MOVING SOUTHWARD OVER
THE NEXT 30 HOURS...TO BE NEAR 23N 157W OR NEAR OAHU AND MOLOKAI...
BY TUESDAY EVENING. AS THE UPPER LOW SINKS SOUTHWARD IT WILL LIKELY
CONTINUE PULLING WARM MOIST AIR UP FROM THE TROPICS AND WRAPPING
THIS MOISTURE AROUND ITS NORTHEAST QUADRANT. THIS PUTS THE BIG
ISLAND OF HAWAII IN THE MOST LIKELY POSITION FOR HEAVY RAIN AND
THUNDERSTORMS THROUGH TUESDAY AND INTO TUESDAY NIGHT. THUS A FLASH
FLOOD WATCH HAS BEEN ISSUED FOR THE BIG ISLAND OF HAWAII FOR TONIGHT
AND TUESDAY. THIS WATCH MAY BE EXTENDED TO SOME OR ALL OF THE OTHER
ISLANDS TUESDAY IF NECESSARY.

ISOLATED CONVECTION HAS DEVELOPED FROM MOISTURE IN A CONVERGENCE
BAND EXTENDING SOUTHWEST FROM THE UPPER LOW AND OVER KAUAI AND OAHU.
THESE SHOWERS ARE ON THE LIGHT TO MODERATE SIDE THIS AFTERNOON AND
SHOULD END AFTER DARK. HOWEVER...AS THE UPPER LOW MOVES DOWN OVER
THE CENTRAL HAWAIIAN ISLANDS LATE IN THE DAY TUESDAY INTO TUESDAY
NIGHT...SCATTERED SHOWERS...SOME HEAVY...WITH ISOLATED THUNDERSTORMS
WILL ALSO AFFECT THE OTHER ISLANDS OF MAUI COUNTY AND OAHU...AND
POSSIBLY KAUAI...AS WELL. THESE SHOWERS WILL ALSO BE BRIEFLY
HEAVY...BUT ARE NOT EXPECTED TO CAUSE FLASH FLOODING AT THE PRESENT
TIME. HOWEVER...THIS SITUATION WILL BE CLOSELY WATCHED FOR FURTHER
THREATS OF FLASH FLOODING.

THE DEEP UNSTABLE MOISTURE WRAPPING AROUND THIS UPPER LOW WILL
EVENTUALLY BE PULLED WESTWARD OVER ALL THE HAWAIIAN ISLANDS...
LIKELY LATE TUESDAY NIGHT INTO WEDNESDAY. FORECAST CHARTS ARE
TENDING TO WEAKEN THE UPPER LOW AND KICK IT OFF TO THE EAST OF THE
STATE ON THANKSGIVING DAY...WITH SOME CLEARING LIKELY...AT LEAST BY
AFTERNOON ACROSS THE STATE.

.LONG TERM...AS THE UPPER LOW WEAKENS AND MOVES OFF TO THE EAST...
TRADE WINDS ARE EXPECTED TO BUILD BACK OVER THE STATE THROUGH THE
COMING WEEKEND AND INTO NEXT WEEK. WITH PLENTY OF MOISTURE OFF TO
OUR EAST WITH THE DISTURBANCE IN THE UPPER ATMOSPHERE...EXPECT
TRADES TO BE ON THE WET SIDE INTO EARLY NEXT WEEK.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH FOR BIG ISLAND OF HAWAII TONIGHT AND TUESDAY.
WINTER STORM WATCH FOR BIG ISLAND SUMMITS TUESDAY THROUGH
THANKSGIVING DAY.

BIRCHARD

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 22, 8:44 PM HSTSpecial Marine WarningHFO61 min
Nov 22, 9:35 PM HSTSpecial Marine WarningHFO55 min
Nov 22, 10:24 PM HSTSpecial Marine WarningHFO66 min

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.