EXTENDED FORECAST DISCUSSION NWS WEATHER PREDICTION CENTER COLLEGE PARK MD 1145 AM EDT TUE AUG 09 2016 VALID 12Z FRI AUG 12 2016 - 12Z TUE AUG 16 2016 ...PATTERN OVERVIEW/THREATS AND GUIDANCE/UNCERTAINTY ASSESSMENT... A BROAD AREA FROM THE LOWER MS VLY INTO THE NORTHEAST/MID ATLC WILL SEE A POTENTIAL FOR HVY RNFL DURING THE FCST PERIOD. FLOW AROUND THE WRN PERIPHERY OF A BERMUDA HIGH BUILDING TOWARD THE MID ATLC/SOUTHEAST COAST WILL LEAD TO INTERACTION OF INITIAL LWR MS VLY/CNTRL GULF COAST MSTR AND COMPACT UPR LOW WITH A WAVY PLAINS TO ERN U.S. FRONT SUPPORTED BY A NRN STREAM SHRTWV TROUGH. SPECIFICS OF LOCATION AND TIMING/DURATION OF HEAVIEST ACTIVITY WILL BE DETERMINED BY SMALLER SCALE DETAILS THAT HAVE LOW PREDICTABILITY... BUT AT THIS TIME THERE IS AT LEAST POTENTIAL FOR LOCALIZED MULTI-INCH TOTALS DURING THE FCST PERIOD WITHIN THE AFOREMENTIONED AREA. MEANWHILE THE COMBINATION OF MONSOONAL MSTR... SOME ASSOC WITH JAVIER... ALONG WITH PERIODS OF LOW LVL UPSLOPE FLOW OVER THE SRN HIGH PLAINS... MAY PROMOTE EPISODES OF HVY RNFL OVER THE SRN ROCKIES/HIGH PLAINS. FARTHER UPSTREAM A PROGRESSIVE PATTERN WILL SEE A RIDGE GIVING WAY TO A SHRTWV TROUGH AROUND SUN AND THEN A TENDENCY TOWARD RELATIVELY FLAT MEAN MEAN FLOW... THE MID-LATE PERIOD SHRTWV WILL SUPPORT A MODEST SFC SYSTEM THAT SHOULD BE ACCOMPANIED BY RELATIVELY LGT/SCT PCPN IF ANY OCCURS. THE GREATEST ANOMALIES FOR TEMPS SHOULD BE WITH MINS AHEAD OF THE WAVY FRONT PUSHING E/SE FROM THE PLAINS. DAILY RECORD VALUES FOR WARM MINS MAY BE PSBL ESPECIALLY FRI-SUN ACROSS PORTIONS OF THE EAST AS WELL AS TEXAS. WARM SECTOR HIGHS WILL BE WARM TO HOT BUT GENERALLY NOT QUITE AS EXTREME AS THE LOWS. THE NORTHWEST MAY SEE SOME HIGHS 10-15F ABOVE NORMAL LATE THIS WEEK... WITH THE WEST OVERALL LIKELY TO SEE NEAR TO ABOVE NORMAL TEMPS THROUGH THE PERIOD. THE SRN HIGH PLAINS INTO S-CNTRL MS VLY SHOULD BE MOST CONSISTENTLY BELOW NORMAL FOR HIGHS. WITH BETTER THAN AVG MODEL/ENSEMBLE MEAN AGREEMENT... THE UPDATED FCST INCORPORATES THE 06Z GFS/GEFS MEAN AND 00Z ECMWF/ECMWF MEAN THROUGH THE PERIOD. THE RESULTING FCST OFFERS GOOD CONTINUITY FOR THE OVERALL PATTERN WHILE REFLECTING ONLY TYPICAL RUN TO RUN DETAIL ADJUSTMENTS. THE MOST NOTABLE TREND IN THE GUIDANCE OVER THE PAST DAY HAS BEEN A FLATTER TREND IN GFS/GEFS GUIDANCE WITH THE PROGRESSIVE TROUGH REACHING THE NORTHWEST AROUND SUN. THE FLATTER FLOW COMPARES FAVORABLY TO TELECONNECTIONS RELATIVE TO THE FCST PATTERN ACROSS THE NRN PACIFIC. RAUSCH