EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1208 PM EDT FRI JUL 10 2015 VALID 12Z MON JUL 13 2015 - 12Z FRI JUL 17 2015 ...PATTERN OVERVIEW... AN EXPANSIVE UPPER RIDGE WILL REMAIN ANCHORED OVER TEXAS NEXT WEEK...WHILE MEAN TROUGHING WILL STAY CENTERED ALONG BOTH THE EAST AND WEST COASTS. AT THE SURFACE...MULTIPLE WEAK WAVES OF LOW PRESSURE WILL DEVELOP ALONG A LINGERING FRONTAL BOUNDARY STRETCHED FROM THE NORTHEAST/MID-ATLANTIC COAST TO THE CENTRAL PLAINS...AND A CANADIAN COLD FRONT WILL STEADILY PRESS SOUTH AND EAST ACROSS THE GREAT LAKES AND NEW ENGLAND. ...MODEL EVALUATION/PREFERENCES... EARLY IN THE WEEK...MODELS HAVE COME INTO BETTER AGREEMENT WITH SOME OF THE DETAILS OF SURFACE WAVES DEVELOPING ALONG THE EAST-WEST FRONTAL BOUNDARY LINGERING FROM THE NORTHEAST/MID-ATLANTIC TO THE CENTRAL PLAINS. HOWEVER...UNCERTAINTY INCREASES TOWARDS THE END OF THE WEEK WITH A TROUGH AMPLIFYING OVER THE NORTHWEST. THE GEFS MEAN CONTINUES TO BE ON THE FASTER/FLATTER SIDE OF MODEL SPREAD...WHILE THE ECMWF ENSEMBLE MEAN STILL PREFERS A SLOWER/MORE AMPLIFIED SOLUTION. BOTH THE LATEST NAEFS AND CMC ENSEMBLE MEAN LEAN TOWARDS MORE AMPLIFICATION...SO THE GEFS MEAN WAS ELIMINATED FROM THE FORECAST BLEND. ...SENSIBLE WEATHER HIGHLIGHTS... THE LINGERING FRONTAL BOUNDARY WILL HELP FOCUS CONVECTION/HEAVY PRECIPITATION ACROSS THE GREAT LAKES/OHIO VALLEY/NORTHERN MID-ATLANTIC STATES EARLY NEXT WEEK...AND A SECOND AREA OF ENHANCED PRECIPITATION WILL BE POSSIBLE OVER THE CENTRAL/NORTHERN PLAINS WITH ENERGY EJECTING OUT OF THE ROCKIES TOWARDS THE LATER HALF OF THE WEEK. MORE ISOLATED CONVECTION/PRECIP IS EXPECTED IN THE ROCKIES AND INTO THE SOUTHWEST. TEMPERATURES ACROSS THE CONUS SHOULD FALL WITHIN 5-10 DEGREES OF AVERAGE... GENERALLY BELOW AVERAGE IN THE WEST AND NORTHEAST BUT ABOVE AVERAGE THROUGH A GOOD PORTION OF THE SOUTH... WITH MANY DAYS AROUND 100F IN INTERIOR TEXAS. GERHARDT