Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
1200 PM EDT Sun Jul 14 2019
Valid 12Z Wed Jul 17 2019 - 12Z Sun Jul 21 2019
...Tropical Storm Barry to weaken and dissipate prior to this
extended period with remnants to fuel some Northern
Mid-Atlantic/Northeast heavy rains Wednesday/Thursday...
...Overview and Guidance/Predictability Assessment...
...Weather Highlights/Threats...
Tropical Storm Barry made landfall in Louisiana Saturday afternoon
and is forecast to continue to weaken and dissipate by Monday
evening over Missouri/Mid-Mississippi Valley, prior to the start
of the extended forecast. The low will become devoid of tropical
characteristics and will be absorbed in the westerly flow through
midweek. Heavier rain associated with the remnants of Barry will
spread across the northern Mid-Atlantic and Northeast Wednesday
and Thursday.
Over the northern states a quasi-zonal flow pattern will develop.
A series of hard to time disturbances will pass through southern
Canada and the U.S. northern tier states all next week. Showers
and thunderstorms capable of producing locally heavy
convection/MCS activity will sporatically develop and propogate
within a wavy frontal/baroclinic zone across the Northern Plains,
Upper Mississippi Valley and into the Upper Great Lakes region,
then into the Lower Great Lakes and Northeast. There will likely
be multiple periods where rainfall amounts/or rates become locally
excessive as the moisture and instability pooling frontal boundary
stalls over the region.
Summertime ridging over southern and central portions of the U.S.
will spread over much of the Southwest and Southern and Central
Rockies. These areas are mainly expected to be mostly warmer and
drier through this coming week. Some locations may tie or set new
daily high minimum records. Heat indices will be around 105 to
115F, which may lead to some future issuance of heat advisories.
Overall, a blend of the reasonably well clustered 06 UTC GFS/GEFS
and 00 UTC ECMWF/ECMWF offers a good first basis for this medium
range forecast.
Schichtel
Additional 3-7 Day Hazards information can be found on the WPC
medium range hazards chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php
WPC medium range 500mb heights, surface systems, weather grids,
quantitative precipitation, winter weather outlook probabilities
and heat indices are at:
https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif
https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html
https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml
https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4
https://www.wpc.ncep.noaa.gov/heat_index.shtml