EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1132 AM EDT SAT MAY 28 2016 VALID 12Z TUE MAY 31 2016 - 12Z SAT JUN 04 2016 THE 28/00Z GFS/ECMWF DETERMINISTIC GUIDANCE SUPPORTS NEARLY ALL THE SYNOPTIC-SCALE FEATURES THIS MEDIUM RANGE PERIOD. THE ONE CHALLENGE IS---HOW TO HANDLE THE SUB-SYNOPTIC SCALE ENVIRONMENT---OVER THE SOUTH CENTRAL PLAINS ON DAY 4. THE GFS CARRIES A CONSIDERABLY STRONGER MID-LEVEL VORTICITY CENTER (SPAWNED BY CONVECTION) ACROSS OKLAHOMA---AND ITS EAST-NORTHEASTWARD MIGRATION ACROSS THE MID-MS VALLEY DAY 5. OTHERWISE...THE NATIONAL FORECAST AND BLEND (USED FROM THE MIDSHIFT) COULD EASILY BE CARRIED FORWARD THROUGH DAY 5. FOR DAY 6-7...ATTENTION WILL LIKELY SHIFT TO THE EXTREME WESTERN GULF OF MEXICO AND A "RE-POSITIONING' OF THE UPPER-LEVEL FLOW AND DIFFUSE TROUGH---FROM ITS CURRENT POSITION INVOF 75W LONGITUDE. THE CATALYST BEING---A MIGRATORY RIDGE OF HIGH PRESSURE ALOFT TRANSITING THE INTERMOUNTAIN WEST ON DAY 6. A BLEND OF THE 28/00Z ECENS/NAEFS WILL SUFFICE FOR NOW---WITH 588DM HEIGHTS ATTEMPTING TO SETTLE ACROSS THE FOUR CORNERS. OF NOTE---THE DETERMINISTIC ECMWF SUGGESTS A CLOSED 594DM ANTICYCLONE CENTER OVER SOUTHERN NEVADA AT 4/00Z. THE DETERMINISTIC GFS---588DM+ HEIGHTS---BUT LOCATED INVOF 110W (COLORADO DIVIDE). THE GENERAL SENSIBLE WEATHER PATTERN FOR THE LOWER 48 REMAINS VERY 'SUMMER-LIKE. SUBSIDENCE ALOFT DRIVING THE MARINE LAYER AND THERMAL TROUGH MOVEMENTS ALONG MUCH OF THE WESTERN COAST OF NORTH AMERICA. TD 'TWO' (AT THE MOMENT) AND ITS INTERACTION WITH A STATIONARY BOUNDARY 'DRAPE' TO ITS NORTH---AND AN ACTIVE CANADIAN FRONTAL PROGRESSION FROM THE DIVIDE SPREADING SOUTH AND SOUTHEASTWARD INTO THE SOUTHERN PLAINS AND CENTRAL MIDWEST/MID MS VALLEY RESPECTIVELY. VOJTESAK