Small Craft Advisory 1, NWS Honolulu, HI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
747 PM HST THU JAN 7 2016

.SYNOPSIS...
A WEAK SURFACE RIDGE OF HIGH PRESSURE WILL SETTLE SLOWLY
SOUTHWARD OVER THE ISLAND CHAIN TONIGHT THROUGH FRIDAY. A COLD
FRONT WILL APPROACH FROM THE NORTHWEST FRIDAY NIGHT...THEN PUSH
SOUTHWARD INTO THE CENTRAL ISLANDS SATURDAY AND SATURDAY NIGHT.
THE FRONT WILL DISSIPATE ON SUNDAY...WITH WEAK HIGH PRESSURE THEN
BECOMING RE-ESTABLISHED OVER THE ISLANDS THROUGH THE MIDDLE OF
NEXT WEEK. ANOTHER WEAKENING COLD FRONT WILL APPROACH THE ISLAND
CHAIN FROM THE NORTHWEST LATE NEXT WEEK.

&&

.DISCUSSION...
CURRENTLY AT THE SURFACE...A FRONTAL BOUNDARY HAS STALLED OUT
AROUND 135 MILES TO THE NORTHWEST OF KAUAI. MEANWHILE...A 1024 MB
AREA OF HIGH PRESSURE IS CENTERED AROUND 1450 MILES EAST-NORTHEAST
OF HILO...WITH A RIDGE AXIS EXTENDING WESTWARD JUST TO THE NORTH
OF THE ISLAND CHAIN. INFRARED SATELLITE IMAGERY SHOWS CLEAR SKIES
IN PLACE ACROSS MOST OF THE STATE...WITH AREAS OF ENHANCED CLOUD
COVER SEEN OVER WINDWARD SECTIONS OF THE BIG ISLAND AS WELL AS
OVER AND TO THE SOUTH OF KAUAI AND NIIHAU. RADAR IMAGERY SHOWS
RAIN FREE CONDITIONS ACROSS MOST OF THE STATE...WITH A FEW SHOWERS
OVER WINDWARD SECTIONS OF THE BIG ISLAND AND OUT OVER THE COASTAL
WATERS. MAIN SHORT TERM CONCERN FOR TONIGHT REVOLVES AROUND RAIN
CHANCES.

TONIGHT...
THE HIGH PRESSURE RIDGE AXIS WILL SLOWLY SETTLE SOUTHWARD AND
INTO THE NORTHERN ISLANDS OVERNIGHT...WITH LIGHT WINDS AND LAND
BREEZES EXPECTED IN MOST LOCATIONS. LIGHT SOUTHEASTERLY STEERING
FLOW OVER THE EASTERN ISLANDS MAY ALLOW A FEW SHOWERS TO DRIFT
INTO WINDWARD EAST AND SOUTHEAST SECTIONS OF MAUI AND THE BIG
ISLAND. FURTHER WEST...LIGHT SOUTH AND SOUTHWEST STEERING FLOW MAY
ALLOW A FEW LIGHT SHOWERS TO MOVE OVER KAUAI AND NIIHAU AS WELL.
ELSEWHERE...RAIN FREE CONDITIONS ARE EXPECTED TO PREVAIL.
OVERNIGHT LOWS NEAR THE COAST ARE EXPECTED TO BOTTOM OUT IN THE
60S TO AROUND 70 DEGREES.

FRIDAY...
A COLD FRONT WELL NORTHWEST OF THE STATE WILL BEGIN TO APPROACH
FROM THE NORTHWEST...AND THIS WILL SHIFT THE HIGH PRESSURE RIDGE
AXIS SLOWLY SOUTHWARD AND OVER THE BIG ISLAND BY FRIDAY EVENING. A
LIGHT WIND REGIME WILL REMAIN IN PLACE ONCE AGAIN...WITH DAYTIME
SEA BREEZES EXPECTED IN MOST AREAS. ANOTHER DRY DAY IS EXPECTED IN
MOST AREAS...WITH ISOLATED SHOWERS POSSIBLE ACROSS THE INTERIOR OF
THE ISLANDS DURING THE AFTERNOON HOURS. THERE MAY BE MORE SHOWER
ACTIVITY ACROSS KAUAI...WHERE DEEP LAYER MOISTURE WILL BE ON THE
INCREASE IN ADVANCE OF THE APPROACHING FRONT. HIGH TEMPERATURES
NEAR THE COAST ARE EXPECTED TO TOP OUT IN THE UPPER 70S TO LOWER
80S.

FRIDAY NIGHT THROUGH SUNDAY NIGHT...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST FRIDAY
NIGHT...REACHING A LOCATION AROUND 125 MILES TO THE NORTHWEST OF
KAUAI BY DAYBREAK SATURDAY. THE COLD FRONT WILL THEN SHIFT
SOUTHWARD THROUGH KAUAI AND OAHU ON SATURDAY AND STALL OUT OVER
MAUI COUNTY SATURDAY NIGHT. THE FRONT WILL THEN DISSIPATE OVER THE
CENTRAL ISLANDS ON SUNDAY...WITH HIGH PRESSURE BECOMING RE-
ESTABLISHED OVER THE STATE SUNDAY NIGHT.

AS FOR FORECAST DETAILS...EXPECT AN INCREASE IN SHOWER ACTIVITY
ALONG AND IN ADVANCE OF THE FRONT AS IT PUSHES INTO THE ISLANDS. THE
SHOWERS ARE EXPECTED TO SHIFT FROM NORTHWEST TO SOUTHEAST DOWN THE
ISLAND CHAIN FRIDAY NIGHT...ALTHOUGH THEY LIKELY WILL NOT MAKE IT
INTO MAUI COUNTY UNTIL LATE FRIDAY NIGHT AND THE BIG ISLAND SHOULD
REMAIN RAIN FREE. THE SHOWER ACTIVITY SHOULD FOCUS PRIMARILY ACROSS
OAHU AND MAUI COUNTY ON SATURDAY...WITH CONDITIONS DRYING OUT ACROSS
KAUAI IN THE AFTERNOON...AND THE BIG ISLAND EXPERIENCING ISOLATED
SHOWERS DUE TO DAYTIME HEATING. AS THE FRONT STALLS OUT AND LIGHT
TRADE WINDS RETURN SATURDAY NIGHT...EXPECT THAT SHOWERS WILL FOCUS
PRIMARILY ACROSS WINDWARD/MAUKA SECTIONS OF THE SMALLER
ISLANDS...WHILE MAINLY DRY CONDITIONS CONTINUE ACROSS THE BIG
ISLAND. A MORE DIURNAL SHOWER PATTERN WILL RETURN SUNDAY AFTERNOON
AND SUNDAY NIGHT AS HIGH PRESSURE BECOMES RE-ESTABLISHED...WITH
ISOLATED SHOWERS FOCUSING ACROSS THE INTERIOR OF ISLANDS DURING THE
AFTERNOON/EVENING HOURS.

MONDAY THROUGH NEXT THURSDAY...
THE HIGH PRESSURE RIDGE AXIS WILL REMAIN CENTERED NEAR OR OVER
THE ISLAND THROUGH MUCH OF NEXT WEEK...WITH A COLD FRONT TRYING TO
APPROACH FROM THE NORTHWEST BY LATE IN THE WEEK. EXPECT A FAIRLY
DRY EL NINO DRIVEN PATTERN TO CONTINUE ACROSS THE STATE THROUGH
THE PERIOD...WITH ISOLATED SHOWERS POSSIBLE EACH DAY MAINLY DURING
THE AFTERNOON/EVENING HOURS ACROSS THE INTERIOR OF THE ISLANDS.

&&

.AVIATION...
LAND BREEZES WILL PREVAIL AT NIGHT...AND SEA BREEZES BY DAY.
SHOWERS SHOULD REMAIN MOSTLY ISOLATED AND LIGHT.

&&

.MARINE...
A SERIES OF LARGE NORTHWEST SWELLS WILL CONTINUE TO IMPACT NORTH
AND WEST FACING SHORES OVER THE NEXT WEEK. A NEW NORTHWEST SWELL
IS EXPECTED TO ARRIVE FRIDAY...BRINGING ADVISORY LEVEL SURF TO
NORTH AND WEST FACING SHORES. ANOTHER LARGER NORTHWEST SWELL WILL
ARRIVE SATURDAY BOOSTING SURF TO WARNING LEVELS. ANOTHER ROUND OF
WARNING LEVEL SURF WILL BE POSSIBLE AGAIN EARLY NEXT WEEK.

WINDS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT ADVISORY /SCA/
CRITERIA THROUGH LATE NEXT WEEK. COMBINED SEAS WILL INCREASE TO 10
FEET OR MORE WITH THE UPCOMING NORTHWEST SWELLS. AS A RESULT...SCA/S
WILL LIKELY BE NEEDED FOR AREAS EXPOSED TO NORTHWEST SWELL SATURDAY
THROUGH EARLY NEXT WEEK.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

DISCUSSION/MARINE...JELSEMA
AVIATION...RYSHKO