Forecast Discussion for BUF NWS Office
FXUS61 KBUF 141425

Area Forecast Discussion
National Weather Service Buffalo NY
925 AM EST Fri Dec 14 2018

High pressure will slide off the New England coast which will bring
milder air to our region today and through the weekend. A weak
trough may bring a few showers to areas near the Canadian border
today. Low pressure over the southeastern states will then move up
along the East Coast for the weekend and will bring a chance of some
rain, especially to the Southern Tier.


A mid level shortwave will move from the Upper Great Lakes to
western Quebec today, with a trailing weak low level trough glancing
our region. Increasing moisture, convergence, and warm advection
along and ahead of the trough axis will bring a period of thicker
cloud cover. Model consensus suggests the southern fringe of an area
of rain will clip the Lake Erie shore and Niagara Frontier from mid
morning through early afternoon, and also areas near the Saint
Lawrence Valley in the afternoon. Farther south and east it will
remain dry. Otherwise, today will be notably warmer, with highs in
the mid 40s on the lake plains of Western NY with a little boost
from modest SSW downslope winds.

Tonight, low pressure will track into the mid-Atlantic states. The
far northern fringe of rain associated with this system may reach
the NY/PA border tonight, while the rest of the area will
remain dry. This system will help maintain a fair amount of
cloud cover in our region, especially across southern portions.
However, with light winds and increasing moisture moving across
the snow pack any areas which do clear out are likely to fog in
quite quickly. The best chance for this to happen is across the
Niagara Frontier and Western Southern Tier.


A closed upper level low will meander from across the Tennessee Valley
Saturday to the southern mid Atlantic states on Sunday. Meanwhile at
the surface an area of high pressure centered over Quebec and
northern New England will suppress the northward extent of the
precipitation shield associated with this upper level low...while
also supplying dry air across our region. It will not be until
Saturday night that the upper level low will drift far enough
northward, and falling precipitation is able to over come a dry low
level for precipitation to reach the ground across our So. Tier.
Light precipitation will spread northward Sunday, though likely
remaining along and south of Lake Ontario.

The surface high to the north will also bring cool air at the lower
levels across our region such that the falling rain may encounter a
subfreezing surface. Will continue the mention for chances for
freezing rain Saturday night and Sunday...though no headlines at
this time due to the still uncertainty to the exact northward extent
of the precipitation shield.

As the closed low is captured by the mean upper level flow aloft
Sunday and Sunday night, it will increase in speed towards the New
England coastline. A brief period of dry weather is expected later
Sunday between this departed upper level low, and the next system to
near us from the west. A shortwave trough now within the northern
branch jet will then dip towards our region Sunday night. This
trough will bring chances for now primarily snow showers Sunday
night across the region.

As the upper level trough swings across the region Monday synoptic
snow showers will expand across the entire region, with lake effect
snow likely along the southern and southeastern Lake Ontario
shoreline. Low level moisture and lapse rates are still not optimal
for a major lake effect response, though lake induced equilibrium
levels climbing to near 10K feet may allow for a moderate lake
effect band briefly southeast of Lake Ontario. Coupled with cold air
advection a brisk west-northwesterly wind will become gusty with
gusts through the day nearing 25 to 35 mph.

Behind the upper level trough Monday night a northwest flow will
continue lake clouds and light lake snows to the southeast of the
Lakes. With the core of the cold pool overhead, overnight lows will
dip 10 to 15 degrees colder than the previous night.


An upper level ridge will cross the region this period, continuing a
rather quiet period for our region...this at a time when we
typically are very active in the snow department. A few lake effect
snow showers will linger Tuesday, mainly southeast of Lake Ontario
on a northwest flow. As the ridge passes us Wednesday expect a dry
day with perhaps a fair amount of sunshine. This ridge will slide
eastward Thursday and we could see the impacts of the next weather
system...this approaching us from the Midwest with a mix of rain and


A weak trough will pass north of the region today. The bulk of
the more organized rain will remain across southern Ontario,
although a few showers may clip KIAG/KART this morning. Expect
mainly VFR conditions, with some MVFR possible from patchy
lower clouds.

Tonight, low level moisture will increase a bit with IFR
stratus and possibly some fog developing across the Niagara
Frontier or Western Southern Tier. Considerable cloud cover will
limit the extent of the fog, but areas which do clear out should
fog in rather quickly with light winds and lots of low level
moisture. This may result in IFR or lower conditions at some


Saturday...Mainly VFR with a chance of rain showers.
Sunday...Mainly VFR.
Monday and Tuesday...VFR with a chance of snow showers.


Southeast to south winds will remain on the lakes through tonight,
but are likely to remain just below small craft thresholds. Another
storm system will near the region for the weekend, though north
winds associated with this system may remain light enough to
continue favorable boating conditions.





LONG TERM...Thomas

NWS BUF Office Area Forecast Discussion