EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1028 AM EST TUE JAN 14 2014 VALID 12Z FRI JAN 17 2014 - 12Z TUE JAN 21 2014 ...OVERVIEW AND PREFERENCES... AMPLIFIED WESTERN RIDGE AND EASTERN TROUGH PATTERN IN PLACE AT THE START OF THE MEDIUM RANGE... FRI/D3... SHOWS NO URGE TO MOVE MUCH BY TUE/D7 AS SHORTWAVES MOVE THROUGH THE LONGWAVE FLOW. MODELS/ENSEMBLES AGREE ON THE SYNOPTIC EVOLUTION BUT CONTINUE TO DIFFER ON THE SPEED/AMPLITUDE OF THE EMBEDDED SYSTEMS. THE GFS/GEFS MEMBERS ARE LARGELY QUICKER AND LESS AMPLIFIED THAN THE ECMWF/ECENS MEMBERS WHICH ARE ALSO CLUSTERED NEAR THE UKMET/CANADIAN RIGHT FROM FRI/D3 AS THE SHARP TROUGH IN THE EAST EXITS THE OH VALLEY. LAG TIME IS ABOUT 12 HRS /GFS-ECMWF/ THROUGHOUT THE PERIOD. THE DETERMINISTIC ECMWF HAS SHOWN ITS INCONSISTENCIES IN SEVERAL AREAS OVER THE PAST FEW CYCLES BUT OVERALL ITS 00Z RUN WAS A GOOD FIT TO THE EXPECTED PATTERN BASED ON THE LATEST 00Z ECENS MEAN. USED A 50/50 BLEND AS THE BASE FOR THE FORECAST. BY TUE/D7... THE ENSEMBLES INDICATE THE POTENTIAL FOR ENERGY IN THE EASTERN PACIFIC TO SEPARATE ALONG 140W WHICH MAY MAINTAIN MORE RIDGING IN THE PAC NW THAN WHAT THE 00Z ECMWF DEPICTS /SHOWING A MUCH STRONGER SHORTWAVE/... BUT ENSEMBLE SPREAD IS QUITE HIGH. OPTED TO RELY MUCH MORE ON THE ECENS MEAN BY THEN GIVEN THE LOWER CONFIDENCE. ...SENSIBLE WEATHER HIGHLIGHTS.... THE PATTERN FAVORS ABOVE NORMAL TEMPERATURES IN THE WEST WITH NO DROUGHT RELIEF FOR CALIFORNIA /ZERO MEMBERS GIVE MORE THAN A TRACE OR SO OF PRECIP TO CENTRAL AND SOUTHERN CALIFORNIA OVER THE NEXT SEVEN DAYS/ WHILE THE EAST WILL SEE MORE VARIABLE TEMPERATURES ON EITHER SIDE OF CLIMATOLOGY. PRECIPITATION SHOULD BE CONFINED TO THE CENTRAL/EASTERN STATES WITH A POSSIBLE SNOWSTORM FOR PARTS OF THE NORTHEAST EARLY THIS WEEKEND AS DEEPENING LOW PRESSURE MOVES UP ALONG THE NEW ENGLAND COAST. GENERALLY LIGHTER PRECIP SHOULD FOLLOW THE PATH OF A COUPLE AREAS OF LOW PRESSURE ALONG THE NORTHERN TIER. FRACASSO