Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Buffalo New York
655 am EST Friday Mar 7 2014
high pressure will remain ridged across New York and New England
today with a warm southerly flow bringing sunshine and mild
temperatures. A weak cold front will approach tonight with
increasing clouds then cross New York Saturday with a return to
cooler temperatures and a chance for some light snow showers.
A few more weak storm systems may cross our region through the
middle of next week with a chance for some light snow with each.
Near term /through tonight/...
high pressure is centered over Massachusetts this morning and ridged
west across New York and the lower Great Lakes region. This is
continuing to provide our forecast area with mainly clear skies.
Some low stratus is seen on infrared imagery sneaking north toward the PA
border at 12z associated with the northern edge of a storm system
off the Carolina coast. The anticyclonic flow around the New England
high pressure center is bringing some 5-10 knot southerly winds
across western and central New York gusting up to 20 knots on the
southern tier hill tops and down along the Lake Erie shoreline. These
winds are keeping temperatures much more milder this morning than what
we saw yesterday morning.
Through today the high pressure center will shift east out over the
Atlantic under a zonal flow aloft while the Carolina storm system
also shifts off the coast. High pressure ridging will continue to
stretch west across New York through the day keeping our weather dry
and sunny for another day. Besides a second day in a row of nearly
full sunshine we will also see mild temperatures thanks to the
southerly winds and the compressional warming effects as they drop
from the higher terrain of the southern tier to the Lake Shores.
Therefore...the temperature forecast is warmer than forecast
guidance. Highs potentially could top 40 degrees across the Niagara
Frontier and the southern tier and Genesee river valleys. Elsewhere
temperatures look to top out in the middle to upper 30s.
Tonight a weak cold front will shift from the upper Great Lakes
east and just about reach western New York by 12z. Clouds will
thicken and lower overnight ahead of the front. Temperatures will
remain mild overnight only falling into the middle to upper 20s with
southerly flow ahead of the front and increasing cloud cover. Light
snow may reach far western New York by daybreak.
Short term /Saturday through Sunday night/...
the weather will be fairly benign through the weekend...although
there will be several chances for light nuisance snow at times.
A cold front will push south across the region Saturday morning. The
front will have little in the way of upper level support with the
middle level shortwave remaining displaced across central Quebec. Even
so...increasing deep layer moisture combined with low level
convergence along the advancing frontal boundary may be enough to
touch off a few scattered flurries and light snow showers. If
anything does materialize it will not add up to much...with a light
coating possible in a few spots. Temperatures should reach the middle
30s in most locations...although cold advection behind the front
during the afternoon may force temperatures to pull back a few degrees
later in the day.
Saturday night into Sunday morning a northwest flow of somewhat
colder air may prove to be just cold enough to support some very
limited lake effect southeast of Lake Ontario. 850mb temperatures bottoming
out around -13c will only support lake induced equilibrium levels of
around 5k feet but this may be just enough for scattered snow
showers southeast of the lake...and also in upslope areas from the
southern tier to The Finger lakes. Amounts will be very light if
anything forms...with a spotty dusting to an inch.
By Sunday afternoon any very limited lake effect southeast of Lake
Ontario should end. Middle level warm advection will increase later in
the afternoon ahead of the next system with thickening middle/upper
level clouds moving into the lower lakes.
Sunday night warm advection will increase as a warm front pushes
east across the region. Latest 00z model guidance remains consistent
in developing some light snow along and northeast of the surface
warm front in the isentropic upglide regime. Snow will be most
likely across the north country where some minor accumulations are
possible...with snow chances decreasing with southern extent towards
the PA state line.
Long term /Monday through Thursday/...
several very potent shortwaves crossing the northern Pacific will
buckle a near zonal flow south of 60n early in this period. The
resulting amplification...as is typically the case...will result
in a much more unsettled weather pattern over the lower 48. This
will certainly be no exception as energy dropping down the front
side of the amplifying West Coast ridge will dive out of The
Rockies and across the Southern Plains where a significant late
winter storm will develop.
The European model (ecmwf) has been suggesting such a storm for a couple days
now...although there has been some inconsistency on the exact track
and timing. This is to be expected from a forecast at this range.
The GFS remains weaker and more suppressed with this system...
keeping the bulk of any significant winter weather well southeast of
our region. The new 00z gefs ensembles show a wide envelope of
timing and track for this system...with several showing a low track
more along the lines of the European model (ecmwf).
The storm system is forecast to spin up in the Lee of the Colorado
rockies Monday night...track across the Southern Plains on Tuesday...
then lift to the northeast across the Ohio and Tennessee valleys
Tuesday night and Wednesday. A fresh push of cold air will arrive
just ahead of this system with temperatures dropping to well below
average once again for Wednesday through the end of the week.
Given the pattern evolution...a significant system is likely across
the central and eastern states...but with plenty of questions
regarding track and timing. All possibilities are on The Table at
this point for western and central New York from dry and cold to a
significant snow event. Will continue to mention the potential in
the severe weather potential statement for now. It will likely still be several days before any
sense of model consistency emerges.
Aviation /12z Friday through Tuesday/...
high pressure will remain ridged across the forecast area through
today providing unlimited VFR and light southerly winds. Toward the
New York/PA state line some low stratus is seen sneaking north this
morning which may reach kelz for a few hours. Otherwise some thin
cirrus may be found along the far northern edge of a storm system
shifting off the Carolina coast. Tonight ceilings will fill and lower
ahead of an approaching cold front from the upper Great Lakes while
remaining VFR. Some light snow may approach far western New York
toward 12z Saturday.
Saturday...VFR/MVFR with a chance of snow showers.
Monday and Tuesday...MVFR/IFR in snow showers.
high pressure will remain ridged across the lower Great Lakes
through tonight. This will continue to provide relatively light
winds and waves remaining below Small Craft Advisory criteria. A
weak front will cross the region Saturday with winds and waves
remaining below Small Craft Advisory criteria.