Extended Forecast Discussion NWS Weather Prediction Center College Park MD 1200 PM EDT Fri Jul 06 2018 Valid 12Z Mon Jul 09 2018 - 12Z Fri Jul 13 2018 ...Weather threats/highlights and Guidance evaluation/preferences... Tropical system activity is quickly escallating over the Atlantic basin. The NHC shows Hurricane Beryl over the tropical Atlantic and continues to follow a disturbance off the southeastern U.S. that offers development potential. WPC progs show a coordinated track for this latter system with the assumption of further development and track off the east coast. Otherwise, an upper high will dominate much of the lower 48 next week. Mean troughs extending down into the Northwest and Northeast flatten then re-amplify again along the US/Canadian border. Heights will become above average coast to coast which supports near to above average temperatures over most areas outside the southern tier. A moderating front in the east will dissipate next week as western North American fronts shift downstream across the northern plains, Upper Midwest/Great Lakes and Northeast along with thunderstorm focus and local severe storm threat as per SPC. The Southwest will see enhanced monsoonal moisture around the upper high realized as precipitation initially over the higher terrain and then into some of the lower deserts. The WPC medium range product suite was mainly derived from a blend of reasonably clustered guidance from the 06 UTC GEFS mean and 00 UTC NAEFS/ECMWF ensemble means through the medium range period. The latest individual models were also reasonably well clustered with ensembles over land, but have been more diverse with tropical based systems. While guidance is coming into better agreement offshore as well, instead prefer to blend the ensemble means everywhere and manually insert current/potential tropical systems as per coordination between WPC and NHC. Schichtel WPC medium range 500 mb heights, surface systems, weather grids, quantitative precipitation, winter weather outlook probabilities and heat indexes are found at: http://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif http://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif http://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html http://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml http://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4 http://www.wpc.ncep.noaa.gov/heat_index.shtml