Flash Flood Warning 24, NWS Honolulu, HI

403 
WGHW70 PHFO 081521
FFSHFO

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE HONOLULU HI
521 AM HST SUN MAY 8 2011

HIC003-081715-
/O.CON.PHFO.FF.W.0024.000000T0000Z-110508T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
HONOLULU COUNTY-
521 AM HST SUN MAY 8 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT FOR THE ISLAND OF OAHU IN
HONOLULU COUNTY UNTIL 715 AM HST...

AT 5 AM HST...ALTHOUGH THE HEAVIEST RAINS APPEAR TO HAVE ABATED 
SOMEWHAT...KAMEHAMEHA HIGHWAY REMAINS CLOSED NEAR THE WAIKANE STREAM 
DUE TO FLOWING WATER AND DEBRIS COVERING THE ROAD. THE OPAEULA AND 
HELEMANO STREAMS ON THE NORTH SHORE REMAINED ABOVE 4 FEET.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO PUNALUU...
WAIAHOLE...WAIKANE...WAIALUA...PUNALUU...LAIE...KAHUKU...HAUULA AND 
HALEIWA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS FLASH FLOODING IS IMMINENT OR OCCURRING
IN STREAMS...ROADS AND LOW LYING AREAS. MOVE TO HIGHER GROUND NOW.

DO NOT CROSS FAST FLOWING OR RISING WATER IN YOUR VEHICLE OR ON FOOT.
TURN AROUND...DON/T DROWN.

&&

RUNOFF FROM THIS STORM MAY ALSO CAUSE ROCK AND MUDSLIDES IN STEEP
TERRAIN.

THIS WARNING MAY NEED TO BE EXTENDED BEYOND 715 AM HST IF FLASH
FLOODING PERSISTS.

LAT...LON 2150 15814 2162 15818 2179 15794 2126 15757
      2124 15772

$$

HUI/HOUSTON

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST SUN MAY 8 2011

.SYNOPSIS...
UNSETTLED WEATHER WITH LOCALLY HEAVY RAINS AND A SLIGHT CHANCE OF
THUNDERSTORMS WILL PREVAIL OVER THE ISLANDS THROUGH TUESDAY
AS AN UPPER LEVEL LOW PRESSURE SYSTEM LINGERS NEAR THE STATE.
THE WINDS WILL DECREASE AND TURN SOUTHEASTERLY TODAY THROUGH MIDDLE
OF THE WEEK AS A SURFACE TROUGH DEVELOPS JUST WEST OF THE ISLANDS.
TRADE WINDS MAY RETURN TOWARDS THE END OF THE WORK WEEK.

&&

.DISCUSSION...
RATHER ACTIVE WEATHER DEVELOPED OVERNIGHT ON OAHU...AND EARLY
MORNING ON KAUAI WITH HEAVY RAINS PERSISTING OVER THE KOOLAU RANGE
AND NORTHERN PORTION OF WINDWARD OAHU...AND EASTERN KAUAI. A JUMP
IN THE RIVER STAGES AS WELL AS HIGH RAIN RATE PROMPTED FLASH
FLOOD WARNINGS FOR BOTH ISLANDS EARLY THIS MORNING. UNSETTLED
WEATHER CONTINUES OVER THE STATE THANKS TO AN UPPER LEVEL LOW THAT
STAYS NEAR THE WESTERN ISLANDS. WITH ABUNDANT MOISTURE IN THE ISLAND
VICINITY...EXPECT RAINY WEATHER TO PREVAIL TODAY WITH LOCALLY HEAVY
RAINS AND A SLIGHT CHANCE OF THUNDERSTORMS. THE SUMMITS OF THE BIG
ISLAND MAY STILL EXPERIENCE PASSING SNOW SHOWERS TODAY...THUS THE
WINTER WEATHER ADVISORY HAS BEEN EXTENDED TO 6 PM HST THIS EVENING.
AT THE SURFACE...THE TRADE WINDS HAVE DECREASED A LITTLE...THOUGH
STILL STRONG ENOUGH TO BRING SMALL CRAFT CONDITIONS TO SELECTED WIND
PRONE CHANNELS AS WELL AS WATERS SOUTH OF THE BIG ISLAND.

ALTHOUGH THE UPPER LEVEL LOW THAT IS CURRENTLY AFFECTING THE ISLANDS
WILL MOVE NORTHWEST...A DEEPENING UPPER LEVEL TROUGH JUST NORTHWEST
OF THE ISLANDS WILL KEEP ATMOSPHERE UNSTABLE OVER THE
STATE...SPECIALLY FOR THE WESTERN ISLANDS IN THE NEXT FEW DAYS. AS A
SURFACE TROUGH DEVELOPS JUST WEST OF THE ISLANDS IN RESPONSE TO THE
DEEPENING UPPER LEVEL TROUGH...THE WINDS WILL CONTINUE TO SLOWLY
DECREASE TODAY THEN TURNING SOUTHEAST TONIGHT. THE SOUTHEAST WINDS
WILL BRING ADDITIONAL TROPICAL MOISTURE UP TO THE ISLANDS THROUGH
THE MIDDLE OF THE WORK WEEK. GIVEN THE GROUND IS ALREADY SATURATED
FROM THE ONGOING RAINS...SPECIALLY FOR KAUAI AND OAHU...THE THREAT
OF FLASH FLOOD IS ELEVATED. A FLASH FLOOD WATCH WILL BE EFFECTIVE
UNTIL MONDAY FOR KAUAI OAHU AND MAUI COUNTY. LOOK FOR UNSETTLED
WEATHER TO PREVAIL THROUGH THE MIDDLE OF THE WEEK...WITH LOCALLY
HEAVY SHOWERS AND A SLIGHT CHANCE OF THUNDERSTORMS AFFECTING ALL
ISLANDS.

LATEST FORECAST CHARTS CONTINUE TO SHOW A RETURN OF TRADE WINDS WITH
IMPROVING WEATHER TOWARDS THE END OF THE WORK AS THE SURFACE TROUGH
IS FORECAST TO MOVE WEST AWAY FROM THE ISLANDS...WHILE A WEAK UPPER
LEVEL RIDGE BUILDS OVERHEAD. THERE ARE DIFFERENCES BETWEEN MODEL
SOLUTIONS ON HOW STRONG THE TRADES WILL BE...THOUGH IT LOOKS LIKE AT
LEAST ALL SOLUTIONS HINT THE RETURN OF TRADE WINDS.

&&

.AVIATION...
WIDESPREAD CLOUDS AND RA WILL CONTINUE TO BRING MVFR CONDITIONS AS
WELL AS MTN OBSCURATION TO KAUAI AND OAHU AT TIMES...AS WELL AS
WINDWARD SITES OF THE OTHER ISLANDS. AIR MASS REMAINS UNSTABLE
FOR ISOL TSRA TO DEVELOP...WITH CB TOPS TO 35 THOUSAND FEET.
AIRMET REMAINS POSTED FOR ICING DUE TO PERSISTENT DEEP LAYER
MOISTURE BUT THE AIRMET FOR TURBULENCE HAS BEEN DROPPED UNDER THE
DECREASING WINDS.

&&

.MARINE...
ELEVATED SEAS UNDER THE STRONGER WINDS CONTINUE TO BRING SMALL CRAFT
CONDITIONS TO PAILOLO AND ALENUIHAHA CHANNELS AS WELL AS MAALAEA BAY
AND WATERS SOUTH OF THE BIG ISLAND. A SMALL CRAFT ADVISORY HAS BEEN
EXTENDED FOR THOSE AREAS THROUGH THIS EVENING. WINDS SHOULD  WEAKEN
ENOUGH BY TONIGHT FOR THE CONDITIONS TO DIMINISH.

A SLIGHTLY LARGER SOUTH SWELL IS EXPECTED TODAY LASTING THROUGH
TUESDAY. A SMALL NORTHWEST SWELL MAY BOOST SURF INTO THE HEAD HIGH
RANGE TODAY...THEN DECLINE MONDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH 6 PM HST MONDAY FOR NIIHAU KAUAI OAHU
MOLOKAI LANAI AND MAUI.

WINTER WEATHER ADVISORY UNTIL 6 PM HST THIS EVENING FOR THE BIG
ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 PM HST THIS EVENING FOR MAALAEA
BAY...PAILOLO AND ALENUIHAHA CHANNELS AND WATERS SOUTH OF THE BIG
ISLAND.

&&

HUI