HAWAII EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 830 AM EDT THU MAY 16 2013 VALID 00Z FRI MAY 17 2013 - 00Z FRI MAY 24 2013 LATEST GUIDANCE CONTINUES TO AGREE IN SHOWING A MODERATE TO LOCALLY BRISK TRADE PATTERN OVER THE NEXT COUPLE OF DAYS WITH HIGH PRESSURE CENTERED TO THE NORTHEAST OF HAWAII. SOME SHORT TERM SHOWERS MAY BE ENHANCED OVER FAVORED TERRAIN UNDER PROXIMITY OF AN UPPER LEVEL WEAKNESS/LOW THAT IS LOSING INFLUENCE. THE MODELS AND ENSEMBLES OFFER SLIGHTLY BETTER THAN NORMAL FORECAST SPREAD/UNCERTAINTY WITH THE DIGGING EXTENT OF ADDITIONAL UPPER LEVEL TROUGH APPROACH FROM THE NW OVER THE WEEKEND THAT WOULD ACT TO DISRUPT TRADES WHILE BRINGING A RAINFALL FOCUSING FRONTAL SYSTEM/INVERTED TROUGH OVER THE STATE. RECENT PATTERN HISTORY AND THE COMMON GUIDANCE BUILDING OF AN AMPLIFIED UPSTREAM UPPER LEVEL RIDGE CONTINUES TO LEND PREFERENCE TO EMPHASIZE AN UPPER LOW POSITION JUST NORTH OF THE STATE SUN-WED THAT IS WELL SUPPORTED BY ENSEMBLES AND THE BULK OF LATEST DETERMINISTIC MODEL RUNS. GUIDANCE OVERALL THOUGH MAY STILL BE UNDERDONE WITH LOCAL ISLAND FOCUS OF POOLED MOISTURE AND RAINFALL POTENTIAL CONSIDERING SOME FAVORABLE ASPECTS OF THE OVERRIDING PATTERN NEXT WEEK. SCHICHTEL