HAWAII EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 755 AM EDT FRI AUG 23 2013 VALID 00Z SAT AUG 24 2013 - 00Z SAT AUG 31 2013 THE MODEL GUIDANCE IS IN GOOD AGREEMENT THAT A PAIR OF TUTT CELLS -- RETROGRADING WEAK UPPER LEVEL LOWS WHOSE VORTICITY PACKETS EMANATE FROM THE MAIN BELT OF THE WESTERLIES -- SHOULD PASS BY THE REGION, WITH THE FIRST PASSING THROUGH THE PAPAHANAUMOKUAKEA MARINE NATIONAL MONUMENT OVER THE NEXT COUPLE OF DAYS AND A SECOND SYSTEM PASSING BY TO THE NORTH OF THE MAIN ISLANDS FROM TUESDAY ONWARD. TRADE WINDS FRESHEN OVER THE NEXT COUPLE DAYS AS A WARM CORE RIDGE BUILDS INTO THE REGION, BEFORE SLACKENING FROM LATE TUESDAY ONWARD AS A NEXT UPPER LOW DRIFTS BY. THE PRECIPITABLE WATER VALUES OVER HAWAI'I REACH A NADIR MONDAY AND TUESDAY UNDER THE WARM CORE RIDGE. OTHERWISE, WINDWARD SHOWERS SHOULD BE EXPECTED FOR EAST AND NORTHEAST FACING SLOPES OF THE ARCHIPELAGO DURING THE NEXT WEEK. ROTH