Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
300 AM EDT Wed Mar 27 2019
Valid 12Z Sat Mar 30 2019 - 12Z Wed Apr 03 2019
...Overview and Weather Highlights and Hazards...
Upper ridging over western Canada will refocus into Alaska to
favor troughing through central/eastern Canada and the Upper
Midwest/Great Lakes/Northeast. Lead low pressure will exit through
the eastern Great Lakes/St. Lawrence Valley this weekend as the
trailing cold front traverses the s-central and eastern U.S.,
lingering across Florida and the Gulf of Mexico. This system may
bring a variety of weather including some weekend snow from the
upper Great Lakes to northern New England and moderate rainfall
and convection ahead of and along the front. A series of southern
stream Pacific shortwaves meanwhile progress underneath into an
unsettled West, then eastward over the U.S. southern tier. This
may invigorate Gulf of Mexico frontal wave genesis next week. This
would lead to increased rains for portions of the Southeast and
especially Florida, leading into possible western Atlantic coastal
low development. Upstream, a renewed system push into the West
Coast early next week may result in periods of moderate rain and
heavier elevation snows from the Northwest to the northern
Rockies.
...Guidance Assessment/Preferences...
The GFS/ECMWF and GEFS/ECMWF ensemble means seem to offer
reasonably similar larger scale pattern evolutions, but less than
stellar consistency with stream interactions and timing/strength
of a multitude of smaller scale systems embedded with the flow.
Prefer a composite blend to mitigate this with blend weighting
transitioning from in favor of these determinitsic models this
weekend to these ensemble means next week.
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