EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1158 AM EDT TUE JUN 23 2015 VALID 12Z FRI JUN 26 2015 - 12Z TUE JUN 30 2015 *** RECORD HEAT IN THE INTERIOR NORTHWEST *** ...OVERVIEW AND GUIDANCE PREFERENCES... MODELS AND ENSEMBLES HAVE COME INTO BETTER AGREEMENT OVER THE PAST 24-36 HRS SHOWING A RATHER IMPRESSIVE/ANOMALOUS AMPLIFIED PATTERN EVOLVING DURING THE LAST FEW DAYS OF JUNE. CONFIDENCE IS NEAR TO ABOVE AVERAGE IN THE SYNOPTIC PATTERN WITH EXPECTED DETAIL DIFFERENCES WITH RESPECT TO SURFACE WAVES ALONG THE FRONT IN THE EAST AND TIMING/DEPTH OF NORTHERN STREAM ENERGY FROM CANADA EARLY NEXT WEEK THROUGH THE UPPER MIDWEST AND GREAT LAKES. RECENT GFS/ECMWF RUNS MOSTLY FALL IN LINE WITH THEIR ENSEMBLE MEANS THOUGH THE 00Z0/06Z GFS SEEM TO DIFFER ENOUGH FROM THE BEST ENSEMBLE LOW CLUSTERING IN THE EAST TO PRECLUDE ITS USE IN THE INITIAL BLEND. HOWEVER... IT OTHERWISE REPRESENTS A REASONABLE FORECAST SCENARIO EVEN OUT TO NEXT TUE/D7. USED A BLEND OF THE 00Z ECMWF/ECENS MEAN AND 06Z GEFS MEAN THROUGH THE PERIOD... WITH A INCREASED ENSEMBLE WEIGHT BY NEXT MON/TUE. ...SENSIBLE WEATHER HIGHLIGHTS... RIDGE/TROUGH PATTERN WILL SUPPORT RECORD HEAT IN THE NORTHWESTERN FIFTH OF THE CONUS... BASICALLY MOST OF WA/OR/ID... WESTERN MT... AND NORTHERN NEVADA. WESTERN REGION SITUATIONAL AWARENESS TABLE SHOWS NAEFS FORECAST ANOMALIES OF 700MB TEMPS AT MAXIMUM OBSERVED /FOR THIS TIME OF YEAR/ IN THE CFSR CLIMATOLOGY /30-YR... 1979-2009... SO NOT NECESSARILY ALL-TIME/. RELATIVE TO THE 00Z GEFS 'MODEL CLIMATE'... FORECAST 850/700MB TEMPS ARE AGAIN AT THEIR MAX FROM WA WHICH SPREADS SOUTHEASTWARD INTO UT. END RESULT IS LIKELY DAILY RECORD HIGH MAX -- AND QUITE POSSIBLE RECORD HIGH MIN -- TEMPERATURES... SOME OF WHICH MAY SURPASS MONTHLY RECORDS. ALL-TIME RECORD HIGHS MAY BE MORE DIFFICULT TO APPROACH BUT MAY COME CLOSE ESPECIALLY AT STATIONS WITH SHORTER PERIODS OF RECORD. IN THE EAST... TROUGHING SHOULD PUSH THE INITIALLY WAVY STATIONARY BOUNDARY SOUTHWARD INTO THE DEEP SOUTH... WITH MUCH COOLER TEMPERATURES THAN THE FIRST PART OF JUNE. PRECIPITATION WILL FOCUS ALONG THIS BOUNDARY. AMOUNTS MAY BE A COUPLE OR MORE INCHES OVER THE WEEKEND FROM THE TN VALLEY EASTWARD TO VA/NC PER THE ENSEMBLES AND GEFS QPF M-CLIMATE / VALUES NEAR RELATIVE MAX IN THE MODEL CLIMATOLOGY/. PRECIP FOCUS IS EXPECTED TO SINK SOUTHWARD AND EASTWARD... LARGELY PUSHING OFFSHORE AS THE BOUNDARY EASES INTO THE ATLANTIC AND ALONG 30N -- WHICH IS PRETTY FAR SOUTH FOR THE END OF JUNE. FRACASSO