EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 118 AM EDT SAT JUL 26 2014 VALID 12Z TUE JUL 29 2014 - 12Z SAT AUG 02 2014 ...AMPLIFIED PATTERN TO DELIVER ANOTHER EARLY FALL-LIKE AIRMASS TO THE CENTRAL/EASTERN STATES... ...OVERVIEW... DEEP TROUGH WILL BE OVER THE EASTERN THIRD OF THE CONUS TO START THE MEDIUM RANGE PERIOD BUT THE LONGWAVE RIDGE/TROUGH ORIENTATION WILL STAY IN PLACE INTO NEXT WEEKEND. RIDGING VIA A STRENGTHENING UPPER HIGH MOVING NORTHWARD THROUGH THE NW ATLANTIC TOWARD NEWFOUNDLAND WILL HELP MAINTAIN THE FAMILIAR PATTERN WITH A WESTWARD RETROGRESSION LIKELY BY SAT AUG 2. OVER THE WEST... RIDGING WILL STAY IN PLACE UNTIL LOWER HEIGHTS OVER THE NE PACIFIC SLOWLY PUSH INTO BRITISH COLUMBIA... SHORTENING THE WAVELENGTH ACROSS THE CONUS. ...GUIDANCE PREFERENCES... THE DETERMINISTIC MODELS HAVE BEEN PERFORMING WELL SYNOPTICALLY WHILE WAVERING A BIT ON THE DETAILS... BUT OVERALL A CONSENSUS BLEND AMONG THE 18Z GFS/GEFS AND 12Z ECMWF/ECENS MEAN HAS PROVEN TO BE A SOLID STARTING POINT. THE UKMET/CANADIAN EMPHASIZED A SECOND SHORTWAVE MOVING THROUGH MICHIGAN AROUND THU THAT MAY BE TOO STRONG IN LIGHT OF THE ENSEMBLE MEMBERS. BY FRI-SAT/D6-7 IN THE WEST... THE ECMWF AND ITS ENSEMBLE MEMBERS ARE A BIT QUICKER TO LOWER HEIGHTS THROUGH BRITISH COLUMBIA AND INTO THE PAC NW THAN THE GFS AND THE GEFS MEMBERS. OPTED TO SIMPLY SPLIT THE DIFFERENCE... WHICH WAS NOT MUCH BY DAY 7 STANDARDS... GIVEN THE RELUCTANCE OF THE PATTERN TO MOVE MUCH AT ALL. ...SENSIBLE WEATHER HIGHLIGHTS... WITH A SIMILAR SETUP TO THE LAST COOL AIR EVENT... AROUND JULY 14-18... MUCH OF THE SAME EFFECTS SHOULD OCCUR... THE CAVEAT BEING THAT THIS WILL NOT BE QUITE AS STRONG AS THE LAST EVENT BUT STILL IMPRESSIVE IN ITS OWN RIGHT. MAX TEMPS SHOULD BE NEAR 10F BELOW CLIMO IN THE EAST BEHIND THE FRONT AND 10-20F BELOW CLIMO IN THE SOUTHERN PLAINS MIDWEEK AFTER THE FROPA IN THE OVERRUNNING PRECIP AREA. IN ADDITION... NW FLOW ALOFT WILL SUPPORT THE CHANCE FOR MCV-LIKE THUNDERSTORM COMPLEX TO TRAVEL SOUTHEASTWARD THROUGH OK/TX INTO LA/AR WED-THU. THE WEST WILL REMAIN WARM/HOT... BUT WITH A TREND TOWARD CLIMO BY NEXT WEEKEND. COLD FRONT THAT WILL BRING THE COOLER AIRMASS TO THE EASTERN TWO THIRDS OF THE CONUS WILL NOT MAKE IT FAR INTO THE WESTERN ATLANTIC AS RIDGING STOPS IT FROM MOVING EAST. ENSEMBLES ALL SHOW UPPER RIDGING PUSHING BACK WESTWARD NEXT FRI-SAT WHICH SHOULD ALLOW THE FRONT TO MOVE WEST AS A WARM FRONT CLOSER TO THE COAST... INCREASING THE CHANCE OF RAIN FROM THE SOUTHEAST UP INTO NEW ENGLAND. FRACASSO