Area Forecast Discussion
Issued by NWS Honolulu, HI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXHW60 PHFO 010136
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST SAT JAN 31 2015

.SYNOPSIS...
GENTLE TRADE WINDS SUNDAY DUE TO A WEAK SURFACE RIDGE NORTH OF THE
ISLANDS WILL GIVE WAY TO SOUTHWEST WINDS MONDAY AS A FRONT
APPROACHES FROM THE NORTHWEST. A SERIES OF FRONTS WILL IMPACT THE
ISLANDS DURING THE UPCOMING WORK WEEK...MAINTAINING WEST TO
NORTHWEST WINDS DURING THE SECOND HALF OF THE WEEK. SHOWERS SUNDAY
WILL BE FOCUSED OVER WINDWARD AND MAUKA AREAS...BUT AS THE VARIOUS
FRONTS REACH THE ISLANDS THIS WEEK...LOOK FOR SHOWERS TO IMPACT
LEEWARD AREAS AS WELL.

&&

.DISCUSSION...
THE RIDGE NORTH OF THE ISLANDS WILL BRING GENTLE TRADES TO THE
ISLANDS THROUGH SUNDAY NIGHT. THIS WILL ALSO KEEP THE LIMITED SHOWER
ACTIVITY CONCENTRATED OVER WINDWARD AND MAUKA AREAS ON SUNDAY. HAVE
BACKED OFF ON THE POPS SOME BASED ON RECENT RAINFALL.

THE GENERAL FORECAST PHILOSOPHY REMAINS THE SAME AS THIS MORNING.
CONTINUING TO PUT A LOT LESS WEIGHT ON THE GFS SOLUTION FOR THE
UPCOMING WORK WEEK FORECAST...AND INSTEAD GOING WITH THE ECMWF
SOLUTION WHICH IS MORE REALISTIC.

THE RIDGE GIVES WAY TO A FRONT APPROACHING FROM THE NORTHWEST ON
MONDAY...WITH WINDS BECOMING SOUTHEASTERLY MONDAY AHEAD OF THE
FRONT. THE FRONT MOVES DOWN THE ISLAND CHAIN MONDAY NIGHT AND
TUESDAY...WITH WINDS SHIFTING TO THE NORTHWEST BEHIND THE FRONT.
GENERAL AGREEMENT WITH THE MODELS SHOWS AN INCREASE IN WINDS
PARTICULARLY WEST OF MOLOKAI WITH THIS SYSTEM. AS THE FRONT MOVES
DOWN THE ISLAND CHAIN...EXPECT SHOWER ACTIVITY TO INCREASE.

IN GENERAL...WEST TO NORTHWEST WINDS WILL RULE AFTER THIS FRONT
PASSES AS A COUPLE MORE FRONTS EITHER PASS OVER THE ISLANDS OR JUST
NORTH OF THE ISLANDS. THE NEXT SYSTEM WOULD MOVE DOWN THE CHAIN
WEDNESDAY AND WEDNESDAY NIGHT...FOLLOWED BY ANOTHER FRONT JUST
NORTHWEST OF THE ISLANDS THURSDAY/FRIDAY. A NEW SURFACE RIDGE BEGINS
TO BUILD IN OVER THE ISLANDS SATURDAY NIGHT...BRINGING LIGHT TRADES
BY SUNDAY. WITH EACH OF THESE SYSTEMS...WE/LL SEE AN UPTICK IN
SHOWER ACTIVITY...WITH MORE DETAILS AS THE EVENT GETS CLOSER.

&&

.AVIATION...
ONSHORE SEA BREEZES WILL GIVE WAY TO OFFSHORE LAND BREEZES TONIGHT
IN SHELTERED LOCATIONS AS THE LIGHT WIND PATTERN CONTINUES. TRADES
ARE STARTING TO FILTER BACK INTO WINDWARD AREAS...BUT WILL REMAIN
LIGHT THROUGH SUNDAY AS A WEAK RIDGE BUILDS NORTH OF THE STATE. THE
TRADE LAYER IS SHALLOW...WITH SOUTHWESTERLY WINDS ABOVE 2000 FT
BASED ON THE LIHUE SOUNDING. CONDITIONS WILL BE PRIMARILY VFR...WITH
OCCASIONAL MVFR CEILINGS IN SHOWERS. MVFR CONDITIONS ARE MORE LIKELY
ACROSS OAHU AND MAUI COUNTY...WHERE GREATER LOW-LEVEL MOISTURE
LINGERS. NO AIRMETS ARE CURRENTLY IN EFFECT AND NONE ARE
ANTICIPATED...UNLESS CLOUDS AND SHOWERS FILL BACK IN GREATER THAN
EXPECTED OVERNIGHT AND BEGIN TO OBSCURE THE MOUNTAINS.

&&

.MARINE...
A HIGH SURF ADVISORY REMAINS POSTED THROUGH TONIGHT FOR THE CURRENT
NORTHWEST SWELL...WHICH SHOULD START TO SUBSIDE SUNDAY. WILL NEED TO
MONITOR THE SWELL AT BUOY 51101 TONIGHT TO SEE IF IT STARTS TO
SUBSIDE. IF IT DOESN/T...THE ADVISORY MAY NEED TO BE EXTENDED.

THE CURRENT SWELL IS ALSO PRODUCING COMBINED SEAS IN EXCESS OF 10
FT...SO A SMALL CRAFT ADVISORY /SCA/ REMAINS POSTED FOR AREAS
EXPOSED TO THE SWELL. WHILE WINDS ARE EXPECTED TO REMAIN BELOW SCA
LEVELS THIS WEEKEND...AHEAD OF THE NEXT FRONT...WINDS MAY REACH SCA
LATE MONDAY PARTICULARLY NEAR KAUAI...OAHU AND MOLOKAI.

&&

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

SMALL CRAFT ADVISORY UNTIL 6 AM HST SUNDAY FOR THE WATERS
SURROUNDING KAUAI...THE OAHU WINDWARD WATERS...THE KAIWI CHANNEL AND
THE MAUI COUNTY WINDWARD WATERS.

&&

$$

DISCUSSION/MARINE...M BALLARD
AVIATION...BRAVENDER





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.