High Surf in Hawaii, March 1 to 6, 2014

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
356 PM HST SAT MAR 1 2014

.SYNOPSIS...
A COLD FRONT WILL MOVE OVER THE STATE TONIGHT...AND REMAIN OVER THE
CENTRAL AND EASTERN PORTION OF THE STATE SUNDAY AND MONDAY.
SHOWERS WILL CONTINUE ACROSS THE SMALLER ISLANDS TONIGHT...SPREADING
TO THE BIG ISLAND SUNDAY AFTERNOON. THE POTENTIAL FOR HEAVY
RAINFALL WILL BEGINS SUNDAY AFTERNOON THROUGH MONDAY DUE TO AN UPPER
TROUGH DIGGING TOWARDS THE STATE. HIGH PRESSURE WILL RETURN TO THE
AREA BY LATE TUESDAY BRINGING NORTHEASTERLY WINDS AND DRIER WEATHER.

&&

.DISCUSSION...
VISIBLE SATELLITE SHOWS A THICK BAND OF CLOUDS ASSOCIATED WITH AN
INCOMING COLD FRONT LOCATED JUST TO THE NORTHWEST OF KAUAI. THIS
FRONT HAS SLOWED DOWN THROUGHOUT TODAY BUT IT IS EXPECTED TO MAKE
ITS WAY ONTO THE ISLANDS TONIGHT AND SUNDAY. MEANWHILE...PRE-
FRONTAL CLOUDS AND SHOWERS ARE IMPACTING THE SMALLER ISLANDS AND
LEEWARD BIG ISLAND LATE THIS AFTERNOON. MOST OF THESE SHOWERS HAVE
BEEN LIGHT TO MODERATE TODAY. AS THE FRONT SLIDES IN
TONIGHT...EXPECT SHOWERS TO CONTINUE FOR THESE SAME AREAS...THEN
SPREAD TO THE BIG ISLAND SUNDAY AFTERNOON.

AS THE FRONT PUSHES DOWN THE ISLAND CHAIN...AN UPPER TROUGH WILL
DIG IN FROM THE NORTHWEST ON SUNDAY. THE AIR MASS OVER THE AREA
WILL BECOME MORE UNSTABLE AND SUPPORTIVE OF LOCALLY HEAVIER
SHOWERS BY SUNDAY AFTERNOON THROUGH MONDAY. THESE HEAVIER SHOWERS
WILL LIKELY BE EMBEDDED WITHIN THE MAJORITY LIGHT TO MODERATE
RAINFALL RATES...SO NOT EXPECTING A FLASH FLOODING THREAT AT THIS
TIME.

HOWEVER...AS THE DEEP LAYERED MOISTURE SUPPORTED BY THE UPPER
TROUGH REACHES THE BIG ISLAND LATE IN THE DAY SUNDAY...THERE WILL
BE THE POTENTIAL FOR SNOWFALL TO THE BIG ISLAND SUMMITS
LATE SUNDAY THROUGH MONDAY. A WINTER WEATHER ADVISORY IS NOT IN
EFFECT FOR THE SUMMITS AT THIS TIME...BUT MAY BE NECESSARY BY SUNDAY
AFTERNOON / NIGHT AS THE THREAT BECOMES MORE IMMINENT. ALSO...A
HIGH WIND WARNING IS IN EFFECT FOR BIG ISLAND SUMMITS THROUGH
MONDAY MORNING DUE TO THE TIGHT PRESSURE GRADIENT ALOFT CAUSED BY
THE DIGGING TROUGH.

MOST OF THE SHOWERS ASSOCIATED WITH THE FRONT WILL PUSH EAST OF
THE SMALLER ISLANDS BY MONDAY AFTERNOON...AND MONDAY NIGHT FOR THE BIG
ISLAND. A SURFACE RIDGE BUILDING FROM THE WEST WILL PROVIDE GENTLE
TO MODERATE NORTH TO NORTHWESTERLY WINDS BEHIND THE FRONT. THE
UPPER TROUGH SITUATED OVER THE ISLANDS MONDAY NIGHT AND TUESDAY
COULD PROVIDE A LITTLE BIT OF ENHANCEMENT TO ANY CLOUDS AND
SHOWERS TRACKING OVER THE STATE AT THAT TIME...BUT THE LACK OF
MOISTURE BEHIND THE DEPARTING FRONT WILL SOMEWHAT LIMIT THE SHOWER
ACTIVITY.

EXPECT A MORE TYPICAL TRADE WINDS WEATHER PATTERN TO ESTABLISH BY
LATE TUESDAY AND WEDNESDAY. WINDS WILL AGAIN VEER SOUTHEASTERLY ON
THURSDAY AHEAD OF ANOTHER FRONT EXPECTED TO ARRIVE FRIDAY NIGHT
INTO SATURDAY.

&&

.AVIATION...
LIMITED AREAS OF MVFR WILL AFFECT THE ISLES THIS AFTERNOON AND
TONIGHT FROM KAUAI TO MAUI AS A FRONT SLOWLY APPROACHES THE STATE
FROM THE WEST. LOWER CEILINGS AND SHOWERS WILL MAINLY HAVE IMPACTS
ON HIGHER ELEVATIONS AND UPSLOPE SECTIONS.

&&

.MARINE...
A VERY LARGE WEST-NORTHWEST SWELL IS BUILDING ACROSS THE STATE
THIS AFTERNOON. A HIGH SURF WARNING IS IN EFFECT FOR EXPOSED NORTH
AND WEST FACING SHORES. THE WARNING HAS NOW BEEN EXTENDED TO COVER
WEST FACING SHORES OF THE BIG ISLAND...THOUGH SURF IS EXPECTED TO
ARRIVE A BIT LATER TONIGHT. THE HIGH SURF WARNING GOES THROUGH 6
AM HST MONDAY MORNING FOR ALL AFFECTED AREAS...SEE CFWHFO ON OUR
WEBSITE FOR MORE INFORMATION.

THIS SWELL WILL PEAK SUNDAY...AND IS LIKELY TO REMAIN ABOVE
WARNING LEVELS THROUGH MONDAY MORNING...AND ABOVE ADVISORY LEVELS
POSSIBLY INTO WEDNESDAY.

THE INCOMING SWELL WILL BRING COMBINED SEAS ABOVE SMALL CRAFT
ADVISORY CRITERIA INTO EARLY NEXT WEEK FOR ALL EXPOSED COASTAL
WATERS. GENTLE WINDS WILL ONLY PLAY SMALL FACTOR IN WAVE HEIGHTS
THROUGH MONDAY. A SMALL BOOST FROM THE TRADE WINDS IS EXPECTED ON
TUESDAY AND WEDNESDAY.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF WARNING UNTIL 6 AM HST MONDAY FOR NORTH AND WEST FACING
SHORES OF NIIHAU KAUAI OAHU MOLOKAI FOR NORTH FACING SHORES OF
MAUI AND FOR WEST FACING SHORES OF THE BIG ISLAND UNTIL 6 AM HST
MONDAY MORNING.

HIGH WIND WARNING UNTIL 6 AM HST MONDAY FOR BIG ISLAND SUMMITS.

SMALL CRAFT ADVISORY UNTIL 6 AM HST MONDAY FOR ALL HAWAIIAN
COASTAL WATERS EXCEPT PAILOLO CHANNEL AND MAALAEA BAY.

&&

DISCUSSION/MARINE...FOSTER
AVIATION...KINEL