Updated LWX discussion:
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Confidence increasing for a high impact winter storm Sunday into
Monday...
Saturday will be the "calm before the storm" as an anomalous region
of high pressure (1040+ mb)resides over the northeast. This will
prime the local region with abundant cold air with many locations
struggling to get above freezing Saturday afternoon.
For the Sunday into Monday system, confidence is continuing to
increase in an impactful storm over at least parts of the region. It
is too early to speculate snow, ice, or rainfall amounts over the
local region as we are still 4-5 days from the event and there are a
lot of moving parts in the atmosphere that will be refined over the
coming days.
Saturday evening, there will be an ULL near the southeast US while
an area of surface low pressure moves north in the parent trough
through the southeast US. Behind this system is another ULL
advecting out of Canada into the great lakes Sunday into Monday
morning. This is resulting in the increasing confidence for a high
impact winter storm. The eventual track, magnitude of WAA at the
surface and aloft, along with other dynamical aspects will determine
where the cold air remains and where the heaviest QPF falls. All
precip types are expected across the region with this storm. The
further west you go in the CWA, the greater the chance for all
frozen precip. Ensemble guidance, deterministic guidance, and the
overall synoptic pattern a plowable snowfall for many at this
juncture. Continue to monitor weather.gov/lwx/winter for the latest
forecast. It should be noted that depending on the ultimate track of
the storm there could be a dry slot moving somewhere over the
region, creating locally lower QPF amounts. A lot will change with
this system over the next 4-5 days.
Aside from the potential hazardous travel conditions due to wintry
precipitation, strong winds may also impact the mountains and
metros. Coastal flooding may also become an issue depending on the
ultimate track of the low pressure system.
A period of upslope mountain snow showers is also likely Monday into
Tuesday as the low moves northeast.