Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
235 AM EDT Tue Jul 03 2018
Valid 12Z Fri Jul 06 2018 - 12Z Tue Jul 10 2018
...Overview and weather threats/highlights...
An expansive upper high will again build back toward the east next
week as brief troughing exits the Northeast Sunday with some
showers/storms prior to its passage. Ensembles remain in great
agreement on a rather zonal flow by next week with above average
heights from coast to coast. This supports near to above average
temperatures nearly everywhere outside the Gulf Coast region where
easterly flow aloft underneath the high will support daily
showers/storms that will be enhanced by an approaching (but
weakening) surface cold front. In the Southwest, moisture out of
the Gulf and across Mexico will try to yield some precipitation
over AZ/NM (GFS/GEFS were wetter than the ECMWF/ECMWF ensembles)
which have been in a serious drought.
...Guidance evaluation/preferences...
A blend of the latest GFS/ECMWF/UKMET and some of the Canadian
offered a good starting point for the forecast. Trend continues to
be quicker across Canada with the least trough/sfc front but
otherwise few changes were made from the previous shift. Increased
ensemble weighting was infused for the later periods where shifts
in the upper high orientation and with rotating mid-level
disturbances were smoothed out.
Fracasso
WPC medium range forecasts of 500 mb heights, surface systems,
weather grids, quantitative precipitation, and winter weather
outlook probabilities 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