High Surf in Hawaii, January 15 to 18, 2015

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST THU JAN 15 2015

.SYNOPSIS...
LIGHT WINDS AND A RELATIVE STABLE ATMOSPHERE WILL CONTINUE TO KEEP
RELATIVELY DRY CONDITIONS OVER THE STATE INTO THE WEEKEND. A FRONT
APPROACHING THE ISLANDS FROM THE NORTHWEST WILL BRING MORE CLOUDS TO
THE ISLANDS THIS WEEKEND...AND A FEW MORE SHOWERS. THE FRONT IS
EXPECTED TO DISSIPATE BEFORE REACHING OAHU. LIGHT TRADE WINDS COULD
RETURN BRIEFLY MONDAY.

&&

.DISCUSSION...
LIGHT AND VARIABLE WINDS WILL CONTINUE INTO THE WEEKEND WITH A HIGH
PRESSURE RIDGE REMAINING OVER THE ISLANDS. THE OVERNIGHT SOUNDINGS
AT BOTH HILO AND LIHUE REPORTED PRECIPITABLE WATER /PW/ VALUES OF
0.79 INCHES...WHICH CONTINUES THE DRY RUN WE/VE BEEN HAVING. THE
MIMIC PW CONTINUES TO SHOW LESS THAN 1 INCH OF PW OVER AND UPSTREAM
OF THE ISLANDS...SO EXPECT DRY CONDITIONS TO CONTINUE.

A COLD FRONT TO THE NORTHWEST OF THE ISLANDS IS MOVING TOWARDS THE
ISLANDS AND WILL REACH KAUAI FRIDAY NIGHT...BEFORE DISSIPATING. THE
MIMIC PW SHOWS A NARROW BAND OF 1 TO 1.5 INCH PW ASSOCIATED WITH THE
FRONT. THE LATEST MODEL RUNS CONTINUE A DRIER TREND WITH THE FRONT
THAN EARLY THOUGHT...SO THE GRIDS/FORECAST HAVE BEEN UPDATED TO
BETTER REFLECT THIS.

AS THE FRONT APPROACHES...IT WILL SHIFT THE RIDGE FURTHER TO THE
SOUTH. AS THE FRONT DISSIPATES...THE RIDGE WILL ONCE AGAIN BECOME
REESTABLISHED JUST NORTH OF THE ISLANDS...WHICH WILL ALLOW FOR SOME
EASTERLY WINDS OVER THE ISLANDS. THESE TRADE WINDS ARE EXPECTED TO
BE LIGHT...AND BRIEF. ANOTHER FRONT APPROACHING FROM THE SOUTHWEST
WILL ONCE AGAIN MOVE THE RIDGE SOUTHWARDS TOWARDS THE ISLANDS
TUESDAY WITH WINDS SHIFTING ONCE AGAIN TO THE SOUTHEAST. BY THURSDAY
NIGHT...LIGHT AND VARIABLE WINDS WILL ONCE AGAIN RULE THE FORECAST.

ALTHOUGH THE LIGHT TRADES WILL HELP TO DISSIPATE SOME OF THE VOG
REACHING THE SMALLER ISLANDS...THEY WILL PROBABLY NOT BE AROUND LONG
ENOUGH TO COMPLETELY CLEAR THE VOG BEFORE THE NEXT ROUND.

&&

.AVIATION...
THE AIRMASS OVER THE STATE REMAINS MOSTLY DRY AND MOSTLY STABLE
UNDER LIGHT FLOW. SCATTERED TO BROKEN STRATOCUMULUS WILL CONTINUE TO
FAVOR THE SOUTHWEST COASTS OF KAUAI AND OAHU AND THE SOUTHEAST
COASTS OF MAUI AND THE BIG ISLAND. BRIEF MVFR CIGS POSSIBLE
OTHERWISE VFR CONDITIONS EXPECTED TO PREVAIL ALL AREAS.

SEA BREEZE DRIVEN CUMULUS ARE EXPECTED TO DEVELOP OVER ISLAND
INTERIORS THIS AFTERNOON...ESPECIALLY LEEWARD BIG ISLAND. SHOWERS
WILL BE LIGHT AND ISOLATED. PARTIAL CLEARING EXPECTED TOWARDS LATE
EVENING AND CONTINUING OVERNIGHT.

NO AIRMETS IN EFFECT AT THIS TIME AND NONE ANTICIPATED.

&&

.MARINE...
A HIGH SURF ADVISORY REMAINS POSTED FOR THE CURRENT NORTHWEST SWELL.
ANOTHER SWELL ARRIVING FRIDAY NIGHT OR SATURDAY WILL BOOST THE SURF
AGAIN...EXTENDING THIS SURF EVENT THROUGH SATURDAY. SURF WILL BE ON
THE DECLINE SUNDAY. A LARGER NORTHWEST SWELL IS EXPECTED TO ARRIVE
DURING THE MIDDLE OF THE UPCOMING WEEK...WHICH COULD PRODUCE WARNING
LEVEL SURF.

ALTHOUGH WINDS ARE EXPECTED TO REMAIN BELOW 25 KNOTS...THE NORTHWEST
SWELLS WILL PRODUCE COMBINED SEAS IN EXCESS OF 10 FEET OVER MOST OF
THE COASTAL WATERS. AS SUCH...A SMALL CRAFT ADVISORY REMAINS POSTED
FOR THE WATERS IMPACTED BY THE NORTHWEST SWELL.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY UNTIL 6 PM HST SATURDAY FOR NIIHAU-KAUAI
WINDWARD-KAUAI LEEWARD-WAIANAE COAST-OAHU NORTH SHORE-OAHU
KOOLAU-MOLOKAI-MAUI WINDWARD WEST-MAUI CENTRAL VALLEY-WINDWARD
HALEAKALA.

HIGH SURF ADVISORY FROM 6 PM THIS EVENING TO 6 PM HST SATURDAY
FOR KONA.

SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI NORTHWEST
WATERS-KAUAI WINDWARD WATERS-KAUAI LEEWARD WATERS-KAUAI CHANNEL-
OAHU WINDWARD WATERS-OAHU LEEWARD WATERS-KAIWI CHANNEL-MAUI
COUNTY WINDWARD WATERS-MAUI COUNTY LEEWARD WATERS-ALENUIHAHA
CHANNEL.

&&

DISCUSSION/MARINE...M BALLARD
AVIATION...BEDAL