Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
257 AM EDT Fri Apr 26 2019
Valid 12Z Mon Apr 29 2019 - 12Z Fri May 03 2019
...Assessment of Model/Ensemble Guidance and Predictability...
Latest GFS/GEFS and ECMWF/ECMWF ensemble solutions seem generally
compatable for much of next week at mid-larger scales, bolstering
overall forecast confidence. However, smaller scale interactions
are leading to less certain frontal wave genesis and track
depictions. The WPC medim range product suite was primarily
derived from a composite guidance blend and the National Blend of
Models, but tilted weighting in favor of the ECMWF/ECMWF ensembles
in consideration of favorable trends from recent GFS/GEFS runs.
...Weather Highlights/Threats...
Passage of multiple shortwaves/height falls in both northern and
southern streams will generate some enhanced rains and mountain
snows for portions of the Great Basin and central/northern
Rockies. These systems will progress downstream and a main weather
focus will develop over the central U.S. Moisture inflow/pooling
into a persistent/slow moving/wavy front will focus multiple
rounds of showers and thunderstorms, with the potential for severe
weather and areas of heavy rainfall. The strongest signal for
heavy rain will be from the Southern/Central Plains to the
Mid-Mississippi/Ohio Valley states. On the northern fringe the
precipitation, sufficient cold air may be in place to support
snows for portions of the Northern High plains and over parts of
the Upper Midwest with low genesis and approach.
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