Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
256 AM EST Sat Dec 09 2017
Valid 12Z Sat Dec 09 2017 - 12Z Mon Dec 11 2017
...Accumulating snow will end across the Southeast while increasing across
the Mid-Atlantic and Northeast...
...Locally heavy lake effect snowfall to continue downwind of the Great
...Critical fire weather persisting across southern California...
A frontal boundary is currently off the East Coast and moving southward
across Florida. Heavy rainfall will continue southward today along the
cold front into South Florida. In addition, there is a marginal risk of
severe weather for South Florida today--with the biggest threat being
strong wind gusts from thunderstorms. See the Storm Prediction Center for
more information. Meanwhile, snow will begin to taper off across the
Southeast and the Carolinas by this morning. The primary surface low will
take shape by this afternoon and lift northward off the Mid-Atlantic
coast. This will bring precipitation--in the form of snow--northward into
the Mid-Atlantic and coastal Northeast/New England this afternoon. As the
low strengthens and lifts northward toward the Canadian maritimes by
Saturday night, snow will quickly taper off the Mid-Atlantic while
increasing across most of the Northeast. As the low moves farther north,
snow will taper off--and will end by Sunday evening.
A series of upper level disturbances will move over the Upper Midwest and
Great Lakes over the next few days. Reinforcing shots of cold air over the
Great lakes will give way to moderate to locally heavy snowfall downwind
of the lakes. On Saturday, the heaviest snowfall is expected to occur
along the UP of Michigan and the eastern shore of Lake Michigan as one
disturbance moves over the region. The lake effect snow activity will
shift to the lower Great Lakes on Sunday. By Monday morning, another
disturbance will slide southward over the Upper Midwest. With cold
conditions in place, the precipitation expected with this system will be
An upper ridge continues to be centered over the West--keeping in place
the warm and dry airmass that has plagued southern California in addition
to strong Santa Ana winds gusting over the region. This, combined with
very low relative humidity, is creating very dangerous fire weather
conditions which will continue at least through the next few days.
Moreover, an inversion will keep smoke trapped across the region--leading
to poor air quality. Please check with the local forecast office for more
information on the warnings and advisories associated with this event.
Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php