High Surf in Hawaii, December 2 to 4, 2015

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
411 AM HST WED DEC 2 2015

.SYNOPSIS...
A PASSING HIGH PRESSURE SYSTEM NORTH OF THE ISLANDS WILL BE
TURNING UP THE TRADE WINDS TODAY...BEFORE BECOMING LIGHT TO
MODERATE DURING THE SECOND HALF OF THE WORK WEEK. A MID LEVEL
RIDGE WILL CONTINUE OVER THE ISLANDS DURING THIS STRETCH RESULTING
IN A RATHER TYPICAL TRADE WIND PATTERN OF MAINLY NIGHT AND MORNING
SHOWERS AND PLENTY OF SUNSHINE DURING THE DAYS. THE WINDS MAY TURN
SOUTHEAST OVER THE WESTERN PART OF THE ISLAND CHAIN EARLY NEXT
WEEK ALLOWING A BIT OF MUGGIER CONDITIONS TO SETTLE IN.

&&

A MODESTLY STRONG SURFACE HIGH PRESSURE SYSTEM OF ABOUT 1026 MB
WILL BE PASSING DUE NORTH OF THE MAIN HAWAIIAN ISLANDS TODAY AND
TONIGHT. THE HIGH IS MOVING EAST AT A RATHER FAST CLIP OF 30
MPH...AND WITH THIS SPEED...THE TRADES WILL RATCHET IT UP RATHER
QUICKLY TODAY...AND COLLAPSE BETWEEN THURSDAY AFTERNOON AND
THURSDAY NIGHT. THE HIGH IS CURRENTLY 1000 MILES NW OF KAUAI
MOVING ESE AT ABOUT 35 MPH. ITS CLOSES POINT TO THE ISLANDS WILL
BE 675 MILES NORTH OF KAUAI THIS AFTERNOON.

THE BOOST IN THE TRADES WILL INCLUDE SOME LOCALLY STRONG AND
GUSTY WINDS TO 40 MPH THIS AFTERNOON THROUGH TONIGHT. IT DOES NOT
APPEARS TO BE A WIND ADVISORY TYPE SYSTEM WHERE YOU HAVE SUSTAINED
WINDS OF 30 TO 39 MPH AND GUSTS OF 50 MPH BUT WILL BE WATCHED
CLOSELY. WE EXPECT THE TRADES TO DROP TO MODERATE SPEEDS BY FRIDAY
AS THE HIGH WILL BE OFF THE CALIFORNIA COAST. LIGHT TO MODERATE
TRADES AND A RATHER DRY PATTERN WILL DOMINATE THE ISLANDS OVER THE
WEEKEND.

A DISSIPATING FRONT CURRENTLY 250 MILES NORTH OF KAUAI IS FORECAST
EASE TOWARD KAUAI DURING THE NEXT 24 HOURS. MODELS ARE STRESSING
THAT THE FRONT WILL STALL JUST OFF THE ISLAND/S NORTH SHORE...
SPARING THE GARDEN ISLE FROM SOME WET TRADES. BUT THERE WILL
BE SOME WIDELY DISPERSE SHOWER BEARING CLOUDS TO GO AROUND AROUND
RIDING IN WITH THE TRADES THAT WILL FAVOR THE WINDWARD AND
MOUNTAIN AREAS. THESE SHOWERS WILL BE MOST ACTIVE DURING THE
NIGHTS AND MORNINGS.

FURTHER DOWN THE ROAD...ANOTHER WEAKENING FRONTAL SYSTEM WILL BE
NEARING THE OFFSHORE WATERS NW OF KAUAI MONDAY NIGHT. ITS PRESENCE
WILL CAUSE THE WINDS OVER THE WESTERN HALF OF THE ISLAND CHAIN TO
VEER SE AND S ON MONDAY. HOWEVER....STRONG RIDGING ALOFT WILL
HELP SUPPRESS CLOUDS FROM THIS CONVECTIVE ENVIRONMENT AND MINIMIZE
THE SHOWERS. THE FRONT NEVER MAKES IT HERE AS IT IS SLATED TO FALL
APART WEST OF KAUAI TUESDAY. ANOTHER FAST MOVING HIGH THEN BUILDS
IN FROM THE WEST...BEHIND THE FRONT...THAT WILL GIVE THE ISLANDS
ANOTHER BOOST OF MODERATE TO STRONG TRADES TUESDAY NIGHT INTO
WEDNESDAY.

&&

.AVIATION...
AIRMET TANGO REMAINS IN EFFECT OVER AND IMMEDIATELY SOUTH THROUGH
WEST OF THE MOUNTAINS ON ALL ISLANDS BELOW 8 KFT DUE TO THE ROBUST
LOW LEVEL TRADE WIND FLOW UNDER RELATIVELY STABLE ATMOSPHERIC
CONDITIONS.

VFR CONDITIONS ARE EXPECTED TO PREVAIL ACROSS MOST AREAS THROUGH
THIS EVENING...ALTHOUGH PASSING LOW CLOUDS AND SHOWERS MAY BRING
BRIEF MVFR CEILINGS AND VISIBILITIES OVER SOME WINDWARD AND MAUKA
AREAS.

&&

.MARINE...
THE NEW NW SWELL IS HERE. THE HANALEI BUOY SHOWS A 9 FOOT SWELL
FROM THE NW AT 15 SECONDS PERIOD....AND APPEARS TO BE MAXING OUT.
THE WAIMEA BUOY LOCATED OFF OAHU/S NORTH SHORE HAS A 6 FOOT SWELL
AT 17 SECONDS. EXPECT A COUPLE OF MORE HOURS OF RISING SWELL WITH
THIS BUOY. THIS NW SWELL WILL CONTINUE TO SPREAD EASTWARD TO THE
OTHER ISLANDS TODAY.

AN EVEN LARGER SWELL IS PREDICTED FOR THIS WEEKEND. THE SOURCE IS
FROM A STORM SYSTEM CURRENTLY LOCATED OFF THE WESTERN END OF THE
ALEUTIAN ISLANDS CHAIN. IT IS FORECAST TO TRACK SE DURING THE NEXT
COUPLE OF DAYS WITH A LARGE FETCH OF GALE TO STORM FORCE WINDS
AIMED AT THE ISLANDS. EXPECT WARNING LEVEL SURF ALONG THE ISLAND/S
NORTH AND WEST SHORES. THE BULLETIN WILL BE ISSUED IN THE NEXT
COUPLE OF DAYS AS THE EVENT DRAWS NEARER.

THE SMALL CRAFT ADVISORY /SCA/ IS CURRENTLY IN PLACE FOR ALL
HAWAIIAN WATERS DUE TO EITHER THE COMBO OF THE SWELL AND/OR WINDS.
THE STRONGER TRADES AND INCREASED SEAS FROM THE INCOMING SWELL
WILL MAKE FOR HAZARDOUS CONDITIONS FOR SMALL CRAFT THROUGH AT
LEAST TONIGHT...WITH GRADUALLY IMPROVING CONDITIONS EXPECTED
STARTING THURSDAY.

&&

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

SMALL CRAFT ADVISORY UNTIL 6 AM HST THURSDAY FOR ALL HAWAIIAN
WATERS INCLUDING MAALAEA BAY.

&&

DISCUSSION/MARINE...LAU
AVIATION...HOUSTON