Wildfire in Hawaii, July 18 to 19, 2015

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
630 AM HST SAT JUL 18 2015

.SYNOPSIS...
A SURFACE HIGH FAR NORTHEAST OF THE AREA WILL KEEP TRADE WINDS
BLOWING THROUGH NEXT WEEK. THE TRADES WILL GRADUALLY SUBSIDE
THROUGH WEDNESDAY...THEN STRENGTHEN AGAIN TOWARD THE END OF THE
WEEK. THE TRADE WINDS WILL KEEP SHOWERS FOCUSED OVER WINDWARD AREAS
THROUGH THE WEEKEND. THE CHANCE FOR AFTERNOON SHOWERS OVER LEEWARD
AND INTERIOR AREAS WILL INCREASE STARTING MONDAY AS THE TRADES
WEAKEN.

&&

.DISCUSSION...
NO CHANGE FROM THE EVENING DISCUSSION. TODAY...SATURDAY...SHOULD BE
A RATHER NICE BUT WARM DAY WITH MODERATE TO LOCALLY STRONG TRADES
BLOWING AND MINIMAL TRADE SHOWERS. THIS STABILITY IS LIKELY
ASSOCIATED WITH A HIGH AMPLITUDE UPPER RIDGE SITTING OVER THE
ISLANDS.

THE SITUATION CHANGES TONIGHT AS A BAND OF SHOWERS APPROACHES THE
ISLANDS FROM THE NE. THE BAND WILL BE AIDED BY A DEEPENING UPPER
LEVEL TROUGH OVER THE ISLANDS. WE DO NOT EXPECT THUNDERSTORMS BUT
WIDESPREAD TRADE SHOWERS FAVORING THE WINDWARD AND MOUNTAIN AREAS
ESPECIALLY AFTER MIDNIGHT. SHOULD NOTE THAT THE ECMWF SOLUTION DOES
NOT SHOW THIS BAND BUT AGREES WITH THE GFS MODEL OF THE DEEPENING
UPPER TROUGH. THE MOISTURE FROM THE BAND WILL LINGER THROUGH
SUNDAY...AND ALONG WITH THE LIGHTER TRADES...WILL END UP WITH
SCATTERED SHOWERS ON THE LEE AND INTERIOR AREAS OF ALL THE ISLANDS.
IN ADDITION TO THESE SHOWERS...A THUNDERSTORM OR TWO MAY POP UP OVER
THE KONA COAST AND UPPER SLOPES OF THE BIG ISLAND INCLUDING THE TWO
SUMMITS.

A DRIER TRADE WIND REGIME RETURNS SUNDAY NIGHT TO MOST ISLANDS AND
PERSIST THROUGH WEDNESDAY OF THE NEW WORK WEEK. THE UPPER LEVEL
TROUGH EVOLVES INTO A CUTOFF LOW SUNDAY NIGHT JUST NORTHEAST OF THE
BIG ISLAND AND DRIFTS WESTWARD PASSING NORTH OF KAUAI MONDAY NIGHT.
ANY SIGNIFICANT WEATHER SHOULD REMAIN NORTH OF THE ISLANDS. FROM
MONDAY THERE ON...THE LIGHT ENOUGH TRADES WILL BRING ON THE LOCAL
SEA BREEZES...AND COUPLED WITH DAY TIME HEATING...WILL END IN SPOTTY
AFTERNOONS CLOUDS AND SHOWERS OVER INTERIOR AND LEEWARD AREAS OF THE
SMALLER ISLANDS. LEEWARD BIG ISLAND WILL MAINTAIN AN ACTIVE RAIN
PATTERN WITH SCATTERED SHOWERS EACH AFTERNOON.

&&

.AVIATION...
VFR CONDITIONS AND MODERATE TRADE WINDS WILL PREVAIL ACROSS THE
STATE TODAY. LOCALIZED MVFR CONDITIONS WILL REMAIN POSSIBLE ACROSS
WINDWARD SECTIONS OF THE ISLANDS EARLY THIS MORNING...AS THE BACK
EDGE OF AN AREA OF DEEP MOISTURE MOVES WEST OF THE STATE. AIRMET
SIERRA FOR MOUNTAIN OBSCURATION HAS BEEN CANCELLED...AND NO AIRMETS
ARE CURRENTLY IN EFFECT.

&&

.MARINE...
THE HIGH RES WIND MODEL SOLUTION POINTS TO TRADES BUILDING TO SMALL
CRAFT CONDITION TODAY FOR THE TYPICALLY WINDY AREAS. ACTUALLY...THE
SMALL CRAFT ADVISORY WAS HOISTED DUE TO REPORTS OF AT OR NEAR SCA
STRENGTH WINDS FROM SEVERAL WIND SENSORS LOCATED STATEWIDE. THIS
ELEVATED TRADES WILL EASE OFF SLIGHTLY TONIGHT AND CONTINUE THROUGH
AT LEAST MID WEEK.

WE ARE AND WILL BE MONITORING CLOSELY THE BUOYS PLACED ACROSS THE
ISLAND/S WINDWARD WATERS FOR THE NEXT SEVERAL DAYS. WE ARE EXPECTING
SURF TO RISE TO NEAR ADVISORY LEVEL ALONG THE EAST FACING SHORES
TODAY. THERE ARE TWO EAST SWELLS...ONE WITH A SHORT PERIOD 11 SECS
AT 5 TO 6 FEET AND A LONGER 13 SECS BUT SMALLER SIZE OF 2 FEET. THE
END RESULT IS MAX SURF OF 7 FEET ALONG THE EAST FACING SHORES. SO
FAR THE READINGS FROM MOST OF THE BUOYS MATCHES UP NICELY WITH WAVE
WATCH. A REINFORCING LONG PERIOD SWELL WILL ARRIVE LATE SUNDAY
NIGHT. A MODERATE SIZE NORTHEAST SWELL OF 11 SECS IS DUE IN ON
MONDAY NIGHT...PEAKING WEDNESDAY.

AN ANTICIPATED INTENSIFYING STORM SYSTEM IN THE SOUTH PACIFIC JUST
EAST OF NEW ZEALAND IN THE NEXT COUPLE OF DAYS...WILL BE GENERATING
A NICE SIZE SWELL TOWARDS HAWAII WITH THE ARRIVAL TIME OF FRIDAY
NIGHT. PLEASE REFER TO PAT/S DISCUSSION FOR MORE DETAILS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR WATERS AROUND MAUI INCLUDING MAALAEA BAY
AND WATERS SOUTH OF THE BIG ISLAND UNTIL 6 AM HST SUNDAY.

&&

DISCUSSION/MARINE...LAU
AVIATION...JACOBSON