586
FXUS61 KBUF 121424
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
1024 AM EDT Wed Mar 12 2025

.SYNOPSIS...
It will be notably cooler today with high temperatures confined to
the 30s and 40s. A frontal boundary will serve as a pathway for a
wave of low pressure that could spread some light mixed rain or wet
snow over parts of the area this afternoon and evening. After this
brief interruption, temperatures will then return to springtime
levels with increasing day to day warmth into the weekend.
Unfortunately, we can also count on a fair amount of rain this
weekend, especially on Sunday.

&&

.NEAR TERM /THROUGH TONIGHT/...
High pressure centered over Quebec will maintain a much cooler
airmass across the region today. Temperatures today ranging from
the mid 40s along the Southern tier to the mid 30s across the North
Country. A quiet start to the day will give way to some increasing
potential for some mixed light rain and wet snow showers by this
afternoon and evening, as a weak wave rides along a lingering
frontal boundary. The airmass in place is quite dry, so not
expecting much in the way of precipitation with the greatest chance
for precipitation along the Southern Tier and western Finger Lakes.

As the surface wave exits tonight the mid level moisture gets
stripped away, with the light precipitation tapering off. Some
higher terrain spots could pick up a coating of snow, but there
should not be any impacts. Otherwise ,it will remain rather cloudy
with temperatures falling to between the lower 30s over the western
counties to the mid 20s east of Lake Ontario.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Zonal flow aloft will persist over the Great Lakes through Thursday
night at the base of a broad upper level trough across eastern
Canada. Two areas of surface high pressure, one over the Canadian
Maritimes and another near Bermuda, will slide eastward and congeal
into a single broad area of anticyclonic flow in the western
Atlantic through Friday. With the nearest low pressure systems well
off to the north over Quebec and to the west across the Plains, dry
weather and modest warm air advection can be expected through this
period.

A warm front draped over the forecast area will lead to a general
N-S temperature gradient over the region Thursday, with highs
ranging from the mid/upper 40s across the North Country to the
upper 50s and low 60s across the Southern Tier and upper Genesee
Valley. Temps will be locally cooler along the southwestern
Lake Ontario and southern Lake Erie shorelines with
northeasterly flow over the waters. Turning much warmer for
Friday with widespread highs in the 60s as southerly flow
deepens across the region. Not out of the question that a few
areas across WNY reach the 70 degree mark, while the North
Country remains a bit cooler overall.

The aforementioned deep low over the central Plains will pivot
northeast to the Upper Midwest Friday night. Showers associated with
this system will hold off until after daybreak Saturday, though the
tightening pressure gradient and increasing LLJ will further deepen
the south-southeasterly flow overnight. This will lead to a night
with lows only in the mid 40s to low 50s and breezy winds,
especially in the typical downslope areas of WNY.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
...Spring Warmth and Soaking Rainfall with Flooding Possible East of
Lake Ontario This Weekend...

Unsettled weather this weekend as several robust shortwaves
partially phase over the Canadian/US Plains region, with the
aggregate longwave trough gradually supplanting the strong ridge of
high pressure extending across the eastern Great Lakes from the
western Atlantic.

The first of these waves and its associated sfc low will be cutting
north-northeast across Lake Superior to open the period Saturday
morning. This will eject a 50kt LLJ and thin ribbon of moisture
eastward across the central Great Lakes and Ohio Valley, with
showers `likely` reaching WNY around mid-morning. With greater
height falls remaining west of the region and the strong offshore
high still in place however, this activity is expected to largely
fall apart as it moves through. Behind the initial round of showers,
a break in the moisture and stronger forcing should also allow for a
dry period back across WNY Saturday afternoon. The aforementioned
jet will lead to a breezy SSE winds especially downwind of the
hilltops. Temps will likewise rise well into the 60s across the
area, with maybe the lone exception of the Tug/Western Dacks.

As another shortwave trough digs southward across the Gulf Coast
Saturday it will tap into a deeper plume of sub-tropical moisture.
This will result in a secondary area of low pressure which will be
rapidly transported northward through the Ohio Valley by a sharp,
cyclonically curved jet streak. It is then expected to merge with
the first low across Southern Ontario through Sunday, resulting in a
deep cold front that will plow through the Midwest and Great Lakes.
Widespread showers and possibly a few thunderstorms associated with
this system will move northeast into the forecast area Saturday
night into Sunday morning, then diminish in coverage as the front
moves through during the daytime hours. High temps Sunday will
likely be in the 60s to near 70 again, though should follow a non-
diurnal trend and fall through the afternoon across WNY.

Concerning the flood potential this weekend (and into early next
week)...NBM probabilities still indicate about a 30-40% chance of
>=1" of rain across far western NY and the Southern Tier over a 24hr
period, with a 50-60% chance east of Lake Ontario across the Tug
Hill. Minimal concerns for impactful rises on the Buffalo area
creeks and streams which have been largely flushed of ice with
little to additional snow pack in the area. The same can not be said
for the Tug Hill region where several feet of snow still remain,
holding up to near 12" of SWE which will be ripe to runoff in
combination with the warm temperatures. This will lead to an
increased risk for river flooding with the primary concern being
on the Black River. Overall probabilities for the river to
reach moderate flood stage at Watertown remain lower compared to
the past couple of days, though the GEFS is more aggressive in
this scenario relative to the NAEFS/HEFS which lean much more
towards minor flood stage.

Once the front moves through Sunday and Sunday night, chances for
additional precipitation sharply fall off as high pressure and dry
air quickly build back in from the west. The strong CAA regime will
allow any additional showers through Monday to mix with and change
over to snow, though chances remain low. Otherwise, it will feel
notably colder compared to the weekend with temps only in the 40s
Monday, though warming again by Tuesday as the high crests east of
the Lakes.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
High pressure will make its way east across Quebec Province today,
keeping VFR weather in place with some mid and high level clouds
through early afternoon.

A returning frontal boundary this afternoon will bring increasing
moisture with a gradually lower of ceilings through the VFR range
into this evening. Some MVFR ceilings will be possible though
across the Southern Tier after 23z. A few rain and wet snow showers
will also become possible south of Lake Ontario with the greatest
potential for these expected to be south of KBUF and KROC.

Tonight...MVFR cigs will be found across the western Southern
Tier with mainly VFR conditions elsewhere. The chances of rain and
wet snow showers will gradually end from west to east.

Outlook...

Thursday and Friday...Mainly VFR.
Saturday...Mainly VFR with a chance of rain showers.
Sunday...MVFR/IFR with rain showers.

&&

.MARINE...
The center of high pressure will drift eastward across Quebec today,
while a frontal boundary slowly edges its way north across the
Ohio Valley. In between these two features, the pressure gradient
will tighten across the lower Great Lakes, resulting in
freshening easterlies and a period of advisory- level conditions
to portions of Lake Ontario west of Hamlin Beach from late this
morning into this evening. Winds and waves will then subside
again as we push through tonight.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 11 PM EDT this evening for LOZ042.

&&

$$

SYNOPSIS...RSH/TMA
NEAR TERM...RSH/TMA
SHORT TERM...PP
LONG TERM...PP
AVIATION...RSH/TMA
MARINE...JJR/TMA