Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
1200 PM EDT Sat Apr 13 2019
Valid 12Z Tue Apr 16 2019 - 12Z Sat Apr 20 2019
...Yet another major spring storm mid-late next week will pack an
excessive rainfall and severe weather threat for the central to
eastern U.S...
...Overview...
Potent upper level troughing will push through the West early week
and dive through the Plains and over the Midwest mid-later week as
ridging comes back to both coasts temporarily in an amplifying
pattern. This supports a robust storm to lift from the southern
Plains to the Great Lakes that holds a threat of excessive rain,
strong winds/severe weather and some Upper Midwest/Great Lakes
snows.
...Guidance Preferences and Weather Highlights/Threats...
Models and ensembles exhibit considerable mid-smaller scale system
variance from run to run, but overall offers reasonably similar
larger scale pattern evolution and amplification next week. A
favored day 3-7 composite blend of the latest GFS/ECMWF mixed with
some GEFS/ECMWF ensemble mean guidance heralds a dynamic energy
track through the unsettled West that leads to yet another
significant storm genesis and weather threat for especially the
central and into the eastern U.S. Significant precipitation will
again increase into Wednesday and spread Thursday/Friday from the
Mississippi/Missouri Valleys through the East with frontal
progression as low pressure strengthens over the Plains and
Midwest. Multi-inch rainfall totals/flooding are probable
(enhanced in embedded convection) in some locations of the warm
sector and to the north/northeast of the low with additional
northern stream support. SPC has issued a day 4-6 severe weather
risk. Temperatures to the north/northwest of the low may only be
marginally cold enough for snow.
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