High Surf in Hawaii, January 4 to 11, 2007

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 AM HST THU JAN 4 2007

.SYNOPSIS...THE TRADE WINDS WILL REMAIN STRONG ACROSS THE ALOHA
STATE TODAY. THESE STRONG TRADES WILL BRING CLOUDS AND SHOWERS TO
WINDWARD AND MOUNTAIN AREAS...AND SOME OF THESE SHOWERS WILL BE
CARRIED OVER TO LEEWARD AREAS OF THE SMALLER ISLANDS. THE TRADE
WINDS WILL GRADUALLY EASE ON FRIDAY AND SATURDAY. AN UPPER LEVEL LOW
IN THE VICINITY OF THE ISLANDS THIS WEEKEND MAY PRODUCE A SLIGHT
INCREASE IN SHOWER ACTIVITY ACROSS PARTS OF THE STATE.

&&

.DISCUSSION...
A 1042 MB SURFACE HIGH IS LOCATED ABOUT 1250 MILES NORTH-NORTHEAST
OF HONOLULU. THIS FEATURE CONTINUES TO MOVE RAPIDLY EAST...BUT IT
WILL SLOW ITS FORWARD MOTION WITHIN THE NEXT 12 HOURS. THE PRESSURE
GRADIENT SOUTH OF THE HIGH WILL LIKELY CONTINUE TO PRODUCE STRONG
WINDS OVER THE ENTIRE ISLAND CHAIN...AND THE SURROUNDING COASTAL
WATERS...THROUGH THIS AFTERNOON. THE WINDS WILL SLOWLY DIMINISH
TONIGHT AND FRIDAY.

A WEAKENING SHEAR LINE REMAINS STALLED JUST NORTH-NORTHWEST OF THE
STATE. SATELLITE IMAGERY AND RADAR REFLECTIVITY DATA CONTINUE TO
SHOW SCATTERED TO BROKEN LOW CLOUDS AND SCATTERED SHOWERS BEING
TRANSPORTED RAPIDLY TOWARD THE WEST-SOUTHWEST ACROSS THE HAWAIIAN
ISLANDS AND THE SURROUNDING COASTAL WATERS THIS MORNING. EXPECT
THESE CLOUDS AND SHOWERS TO CONTINUE TO AFFECT MAINLY WINDWARD AND
MOUNTAIN AREAS...BUT THE STRONG TRADES WILL TRANSPORT SOME OF THE
SHOWERS OVER TO LEEWARD AREAS OF THE SMALLER ISLANDS.

A WEAKENING UPPER TROPOSPHERIC LOW IS CURRENTLY LOCATED ABOUT 450
MILES SOUTH OF HILO. THIS FEATURE ALOFT IS MOVING TOWARD THE
NORTHEAST AT ABOUT 15 MPH. THERE ARE PATCHES OF BROKEN MIDDLE AND
UPPER LEVEL CLOUDS ASSOCIATED WITH THIS SYSTEM. SOME OF THESE CLOUDS
ARE MOVING ACROSS THE BIG ISLAND THIS MORNING.

THE GFS MODEL INDICATES ANOTHER UPPER TROPOSPHERIC LOW WILL DROP
DOWN FROM THE NORTHEAST TO A POSITION NEAR THE ISLANDS BY SATURDAY
AFTERNOON. IF THIS FEATURE ALOFT DOES INDEED DEVELOP...IT WOULD
LIKELY ENHANCE SHOWER ACTIVITY ACROSS MOST OF THE STATE THIS
WEEKEND. THIS LOW IS FORECAST TO GRADUALLY LIFT OUT TO THE NORTHEAST
AWAY FROM THE STATE BY SUNDAY AFTERNOON.

THE LATEST GLOBAL MODEL RUNS CONTINUE TO SHOW A WIDE VARIETY OF
SOLUTIONS REGARDING A SURFACE TROUGH...OR POSSIBLY A SURFACE
LOW...FORMING WEST OF KAUAI BY SUNDAY NIGHT OR MONDAY. FOR
EXAMPLE...THE 06Z RUN OF THE GFS SHOWS A SURFACE TROUGH ABOUT 620
MILES WEST-NORTHWEST OF KAUAI EARLY MONDAY AFTERNOON. THE 00Z ECMWF
RUN GENERALLY AGREES WITH THIS SCENARIO...WHILE THE 00Z NOGAPS RUN
SHOWS A WEAKER TROUGH JUST WEST OF KAUAI AT THAT TIME. NO LARGE
CHANGES HAVE MADE TO THE LATEST FORECAST PACKAGE FOR THE PERIODS
FROM SUNDAY THROUGH MONDAY NIGHT DUE TO THE UNCERTAINTY IN THE
LOCATION AND INTENSITY OF THIS SURFACE TROUGH THAT MAY DEVELOP
SOMEWHERE WEST OF KAUAI. STAY TUNED.

&&

.MARINE...
GALE WARNINGS REMAIN POSTED FOR THE ALENUIHAHA CHANNEL AND THE
SOUTHEAST BIG ISLAND WATERS TODAY. SMALL CRAFT ADVISORIES WILL
REMAIN POSTED THROUGH AT LEAST SATURDAY NIGHT FOR A COMBINATION OF
WINDS AND HAZARDOUS SEAS FOR THE REMAINING HAWAIIAN COASTAL WATERS.
AS A RESULT OF THE STRONG TRADE WINDS...EXPECT LARGE AND ROUGH SURF
NEAR OR ABOVE THE HIGH SURF ADVISORY THRESHOLD OF 8 FEET ALONG EAST
FACING SHORES LATER TODAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY THROUGH THIS AFTERNOON FOR ALL ZONES.

GALE WARNING THROUGH THIS AFTERNOON FOR THE ALENUIHAHA CHANNEL AND
BIG ISLAND SOUTHEAST WATERS.

SMALL CRAFT ADVISORY THROUGH SATURDAY AFTERNOON REMAINING HAWAIIAN
WATERS.

&&

HOUSTON