High Surf in Hawaii, July 20 to 21, 2007

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE HONOLULU HI
505 AM HST FRI JUL 20 2007

UPDATED FOR LATEST INFORMATION ON COSME

.SYNOPSIS...TROPICAL DEPRESSION COSME CONTINUES TO MOVE WEST ON A
TRACK THAT WILL TAKE IT SOUTH OF THE BIG ISLAND TONIGHT. STARTING
LATER TODAY...AND CONTINUING THROUGH SATURDAY...COSME WILL PRODUCE
STRONGER WINDS AND HEAVIER RAIN...ESPECIALLY ON THE BIG ISLAND OF
HAWAII. TRADE-WIND WEATHER WILL RETURN ON SUNDAY AND CONTINUE
THROUGH NEXT WEEK.

&&

.DISCUSSION...AT 500 AM HST...THE CENTER OF TROPICAL DEPRESSION
COSME WAS 400 MILES SOUTHEAST OF HILO...HAWAII...MOVING TOWARD
THE WEST AT 17 MPH. MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH WITH
HIGHER GUSTS. SEE THE BULLETINS FROM THE CENTRAL PACIFIC HURRICANE
CENTER FOR DETAILS ON COSME.

FOR NOW...COSME IS NOT HAVING MUCH IMPACT ON ISLAND WEATHER AND
TRADE WINDS CONTINUE TO BLOW ACROSS THE ISLANDS. SATELLITE IMAGERY
SHOWS SCATTERED LOW CLOUDS UPSTREAM OF THE ISLANDS FROM KAUAI TO
MAUI AND RADAR SHOWS ISOLATED SHOWERS FALLING FROM THESE CLOUDS.
THESE SHOWERS WILL CONTINUE MOVING ACROSS THE SMALLER ISLANDS
OVERNIGHT. SHOWERS WILL BE CONCENTRATED OVER WINDWARD AREAS...BUT
SOME LIGHT SHOWERS WILL SPREAD LEEWARD. THERE ARE ONLY ISOLATED LOW
CLOUDS WITHIN 150 MILES UPSTREAM OF THE BIG ISLAND OF HAWAII AND THE
WINDWARD SIDE OF THE BIG ISLAND WILL BE DRIER THAN USUAL OVERNIGHT.

LATER TODAY...WINDS WILL STRENGTHEN AS COSME APPROACHES FROM THE
SOUTHEAST. COSME WILL PASS CLOSEST TO THE BIG ISLAND SO THE IMPACT
WILL BE GREATEST THERE. WITH A FAIRLY STRONG HIGH NORTH OF THE
ISLANDS...THE PRESSURE GRADIENT WILL TIGHTEN AND WIND SPEEDS WILL
INCREASE ACROSS THE WHOLE AREA. A WIND ADVISORY CONTINUES FOR THE
SUMMITS OF HALEAKALA ON MAUI AND MAUNA KEA AND MAUNA LOA ON THE BIG
ISLAND OF HAWAII AND A SMALL CRAFT ADVISORY CONTINUES FOR PARTS OF
THE COASTAL WATERS. BOTH OF THESE ADVISORIES MAY NEED TO BE EXPANDED
AS COSME GETS CLOSER.

SHOWERY CLOUDS ON THE NORTH SIDE OF COSME WILL REACH THE BIG ISLAND
BY THIS EVENING. AS THIS MOISTURE MOVES UPSLOPE ON THE BIG ISLAND...
HEAVY RAIN IS LIKELY....SO A FLASH FLOOD WATCH CONTINUES FOR THE BIG
ISLAND. IT IS NOT SO CLEAR HOW MUCH COSME WILL AFFECT RAINFALL ON
THE OTHER ISLANDS. HEAVIER RAINFALL IS LIKELY TO SPREAD AT LEAST AS
FAR AS MAUI COUNTY...BUT IT IS TOO SOON TO SAY VERY CONFIDENTLY IF
OAHU AND KAUAI WILL GET MUCH OF AN INCREASE.

&&

MARINE...
AS COSME APPROACHES...SURF WILL INCREASE...SO WE HAVE ISSUED A HIGH
SURF ADVISORY FOR THE EAST-FACING SHORES OF THE BIG ISLAND. AN
ADVISORY MAY BE NEEDED LATER FOR EAST-FACING SHORES OF THE OTHER
ISLANDS. THE SMALL CRAFT WILL PROBABLY NEED TO BE EXPANDED AND GALE
WARNINGS ARE POSSIBLE FOR SOME AREAS.

&&

.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY FOR EAST-FACING SHORES OF THE BIG ISLAND.
SMALL CRAFT ADVISORY FOR PAILOLO AND ALENUIHAHA CHANNELS...MAALAEA
BAY AND WATERS SOUTH OF THE BIG ISLAND.
WIND ADVISORY FOR SUMMITS OF BIG ISLAND AND MAUI.
FLASH FLOOD WATCH FOR THE BIG ISLAND.

&&

DONALDSON