Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
1107 PM EDT Mon Mar 11 2019
Valid 12Z Fri Mar 15 2019 - 12Z Tue Mar 19 2019
...Overview and Guidance Assessment/Preferences...
Upper ridging over the Canadian Rockies will favor broad troughing
over the eastern half of the lower 48 this weekend into early next
week with a dry northwesterly flow after a cold front exits off
the Northeast/Mid-Atlantic coast Friday. That front will settle
into the Florida Straits and maintain a daily chance of rain for
the Sunshine State as well as south Texas. The Pacific Northwest
will likely stay dry until about next Tuesday when a system may
attempt to move closer to the coast. Latest GFS/ECMWF offer good
clustering through the period with expected differences in the
swift NW flow out of Canada. A consensus position was best given
the run-to-run shifts in weak shortwave timing.
...Weather Highlights and Hazards...
As the system exits through Ontario and Quebec on Friday the rain
will push off the coast except for Florida where the front will
slow down on Sat/Sun. Northerly to northwesterly flow across the
largely frozen Great Lakes will produce some lake-enhanced snow
(minimal moisture flux through the ice). Cooler temperatures (5-15
degrees below average) will shift eastward out of the west and
focus on the central states this weekend into next Mon/Tue. The
West Coast will see temperatures rise to about 5-10 degrees above
average.
Fracasso
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