AFDHFO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE HONOLULU HI 830 PM HST SUN JUN 26 2011 .SYNOPSIS... A SURFACE HIGH TO THE NORTH WILL PRODUCE LOCALLY BREEZY TRADE WINDS THROUGH TOMORROW MORNING. A LOW ALOFT IS MAKING THE ATMOSPHERE A BIT UNSTABLE SO SHOWERS WILL BE MORE ACTIVE AND WIDESPREAD TONIGHT THROUGH TUESDAY WITH SOME SHOWERS SPREADING LEEWARD OVER THE SMALLER ISLANDS. THE LOW ALOFT IS ALSO PRODUCING HIGH CLOUDS THAT MAY BE THICK AT TIMES...BUT WON/T BRING ANY RAIN. THE ATMOSPHERE WILL START TO STABILIZE TUESDAY NIGHT AS THE LOW ALOFT MOVES AWAY TO THE WEST AND RIDING ALOFT BUILDS OVER THE ISLANDS. MEANWHILE...THE SURFACE HIGH WILL MOVE AWAY TO THE NORTHWEST. THE TRADE WINDS WILL WEAKEN AND THE WEATHER WILL BECOME QUITE DRY FROM THURSDAY THROUGH NEXT WEEKEND. && .DISCUSSION... A 1028 MB SURFACE HIGH ABOUT 1000 MILES NORTH OF KAUAI WILL MOVE NORTHWEST AND STRENGTHEN OVER THE NEXT FEW DAYS. THIS HIGH WILL PRODUCE LOCALLY BREEZY TRADE WINDS OVER THE ISLANDS THROUGH TUESDAY MORNING. THE TRADES ARE CARRYING SHOWERY LOW CLOUDS OVER THE ISLANDS. UPPER AIR ANALYSES AND WATER VAPOR IMAGERY SHOW A LOW ALOFT 235 MILES NORTH NORTHEAST OF KAUAI NEAR 25N158W. THIS LOW IS FORECAST TO MOVE WEST SOUTHWEST AND DEEPEN. THE LOW KEEP THE ATMOSPHERE OVER THE ISLANDS A BIT UNSTABLE...SO SHOWERS ARE LIKELY TO BE MORE ACTIVE AND WIDESPREAD THROUGH TUESDAY. RIDGING ALOFT WILL BUILD OVER THE ISLANDS FROM THE SOUTHEAST ON WEDNESDAY. THE ATMOSPHERE OVER THE ISLANDS WILL BECOME DRIER AND MORE STABLE AND RAINFALL WILL BECOME SPARSE. AS THE SURFACE HIGH CONTINUES TO MOVE NORTHWEST...THE SURFACE PRESSURE BETWEEN THE HIGH AND THE ISLANDS WILL DROP...AND A SURFACE LOW MAY FORM NORTHWEST OF KAUAI TUESDAY NIGHT. THIS PATTERN WILL DECREASE THE PRESSURE GRADIENT OVER THE ISLANDS AND THE TRADE WINDS WILL WEAKEN. IN THE SECOND HALF OF THE WEEK WE SHOULD HAVE GENTLE TO MODERATE TRADE WINDS AND RATHER WARM DRY WEATHER. && .MARINE... THE SMALL CRAFT ADVISORY REMAINS UP FOR ALL OF THE CHANNELS AND THE USUAL WINDY AREAS AROUND MAUI AND THE BIG ISLAND TONIGHT. WINDS ARE LIKELY TO DROP BELOW THE ADVISORY THRESHOLD IN THE KAUAI AND KAIWI CHANNELS TOMORROW...BUT WILL REMAIN ABOVE ADVISORY LEVELS THROUGH TUESDAY MORNING IN THE WINDIER AREAS AROUND MAUI AND THE BIG ISLAND. && .AVIATION... AIRMET TANGO FOR MODERATE LOW LEVEL TURBULENCE IS IN EFFECT DUE TO STRONG TRADE WINDS. THIS AIRMET MAY REMAIN UP THROUGH TUESDAY MORNING. && .HFO WATCHES/WARNINGS/ADVISORIES... SMALL CRAFT ADVISORY UNTIL 600 AM MONDAY. && $$ DONALDSON