Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
252 AM EST Wed Nov 16 2022

Valid 12Z Wed Nov 16 2022 - 12Z Fri Nov 18 2022

...An intensifying coastal low will produce inland mixed precipitation and
snow; coastal rain across the Northeast through Wednesday...

...Significant Lake Effect Snow event in the Great Lakes downwind of Lake
Erie and Lake Ontario through Friday...

...Strong Santa Ana winds across Southern California subsiding Wednesday
evening...

...Anomalous cold will continue for most of the CONUS through the end of
the week...


An intensifying coastal low is currently producing widespread
precipitation across the Northeast as it moves northeastward, with rain
falling along the coast and a mixture of snow, sleet, and freezing rain
for areas further inland. In higher elevations, including northern Maine,
precipitation will fall in the form of snow for much of the event, leading
to Winter Storm Warnings being issued for the potential for heavy snow
accumulations through Wednesday morning. Elsewhere, minor accumulations
are expected across the interior Northeast, as snow during the early
morning hours will quickly transition to a wintry mix and rain as warm air
surges northward. Regardless, hazardous travel conditions will be
possible, resulting in a swath of Winter Weather Advisories issued from
central Pennsylvania northward into Maine. In coastal sections of the
region, up to an inch of rain is forecast to fall through Wednesday, with
locally higher amounts possible in locations where moderate rainfall
persists. Conditions across the region are expected to improve from south
to north as the system exits into the Canadian Maritimes late Wednesday
evening, with the last of the precipitation winding down in Maine during
the early morning hours of Thursday.

Behind the departing system, a significant Lake Effect snow event is
forecast to develop downwind of Lakes Erie and Ontario as cold
northwesterly flow blows across the warmer-than-normal lake water. Snow is
expected to begin late Wednesday evening before conditions quickly
deteriorate on Thursday, with heavy snow leading to near-impossible travel
conditions due to very poor visibility and snow-covered roads. Total
snowfall accumulations will be highly dependent on where snow bands
develop and could shift significantly with changes in wind direction.
Locations where snow bands persist the longest could receive several feet
of snow through Friday. A cold front will approach the region late
Thursday into Friday, and southwesterly flow ahead of the front will help
to decrease snowfall amounts by pushing snow bands offshore over the
lakes, but periods of lake-effect snow will remain possible each day
through the end of the week.

Furthermore, anomalously cold air continues to grip the nation as high
temperatures are forecast to remain 10-20 degrees below average through
the work week. Locations as far south as the Gulf Coast will experience
high temperatures dipping into the lower 50s and even the upper 40s on
Wednesday and Thursday. On the backside of the upper-level trough swinging
through the Plains, even colder air will filter in from Canada as highs
struggle to get above freezing during the daytime hours this week across
the central U.S.

Lastly, a large pressure gradient across the Great Basin and California
will lead to strong Santa Ana winds in southern California through
Wednesday evening. As a result, High Wind Warnings and Wind Advisories
have been issued for the Transverse Ranges until Wednesday night, where
winds may gust as high as 75 mph.


Russell

Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php