-- Discussion containing changed information from previous version are highlighted. --
885
FXUS61 KBUF 261853
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
253 PM EDT Wed Mar 26 2025

.SYNOPSIS...
The chilly and unsettled pattern will persist through this
evening, with occasional snow showers. High pressure will build
into the area with a return to mainly dry weather tonight and
most of Thursday. Unsettled weather will then return this
weekend with an elongated low pressure system bringing periods
of rain to most of the area, and possibly some mixed
precipitation across the North Country.

&&

.NEAR TERM /THROUGH THURSDAY NIGHT/...
A mid level shortwave axis across northern New York will
continue to move east through this evening. Associated height
falls and moisture will support snow showers this afternoon,
which will taper off from west to east through this evening. Any
additional accumulations will be minor, but snow showers may
briefly lower visibility to less than a half mile. Temperatures
will remain in the 30s this afternoon.

High pressure centered across North Carolina will ridge
northward into the area late tonight. This will promote a
clearing trend overnight, with lows dropping into the 20s.

High pressure will maintain fair and dry weather for the first
half of the day Thursday. It will be warmer, with highs mainly
in the 40s, except across the North Country where it will only
reach the upper 30s. Then low pressure passing by to the north
will push a weak cold front across the region late Thursday
afternoon and Thursday evening. This may produce some rain
showers with its passage, or rain or snow showers across the
North Country. Any showers will be light, with little if any
snow accumulation.

An elongated ridge of high pressure will move across the area
late Thursday night, bringing a return to dry weather and a
partial clearing.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
-- Changed Discussion --
Large-scale flow across the CONUS becomes more zonal this
period. At the same time, an initial southern-stream shortwave
trough will make its way eastward through this developing zonal
flow regime, leading to the development of a broad surface low
across the Plains States Friday and Saturday. Well out ahead of
this low...a surface warm front/tightening baroclinic zone will
gradually extend eastward across the southern Great Lakes Friday
and across our region Friday night. Difference from previous
package is that overall trend in guidance is to continue a
slight shift northward with the surface front/baroclinic zone,
placing the boundary across Lake Ontario and northern NYS for
later Friday night and Saturday.

Between later Friday afternoon and Saturday, this boundary will
serve as the conduit for what appears to be at least a couple weak
eastward-propagating waves of low pressure and associated surges of
warm air advection, which will result in fairly widespread
precipitation along and to its north. With the latest boundary
placement in mind, expect steadier area-wide precipitation first
half of Friday night, to then transition to areas mainly from the
Thruway corridor northward for later Friday night and Saturday.
Otherwise, expect more in the way of showery precipitation to the
south of the boundary.

The key to the forecast during this timeframe continues to be the
position of the surface front, as this will have a huge impact on
both temperatures and precipitation potential/type at any given
location. This said, pinning down the exact location of this feature
remains rather problematic at this vantage point, as our region will
lie either directly within or very close to the battleground between
warmer air trying to advect in from the Ohio Valley...and Canadian
high pressure and much colder air firmly anchored near James Bay.
That stated, subtle differences in the exact positioning of the
boundary persist amongst the various guidance packages.

All of this translates into a significant forecast bust potential,
particularly Friday night through the first half of Saturday, before
warmer air works far enough northward for an all rain p-type across
the bulk of western and northcentral NY by Saturday afternoon. The
exception may linger across the Saint Lawrence valley, where cold
northeasterly drainage flow may continue a threat for some mixed
precipitation toward far northern Jefferson County. Digging a bit
more into the weeds...the front will be the demarcation line between
temps in the 30s/40s to its north and temps in the 50s/60s to its
south. For now the forecast continues to exhibit a marked north-
south dichotomy in temperatures during this timeframe and will
likely need continued refinement over the next couple of days as
forecast details become more clear. Putting it all
together...precipitation across western NY currently appears more
likely to be in the form of just plain rain, while a period of
snow/mixed precipitation appears more likely east of Lake Ontario
(especially the North Country, which should remain on the north (and
colder) side of the surface boundary until at least Saturday
afternoon. Will continue to call the latter just a plain rain/snow
mix for now given the uncertainty, however some freezing rain and/or
sleet certainly appears to be a possibility, mainly across the North
Country.

Saturday night, the aforementioned surface front will try to take a
slight shift back southward as the weak aforementioned waves pull
east of the area. At the same time, another wave will be approaching
from the southwest. This will likely halt any southward progress of
the surface boundary, while also bringing in the next slug of
moisture across our area, with mainly rain expected, although still
can`t rule out the chance for some mixed precipitation toward far
northern Jefferson County.
-- End Changed Discussion --

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
A potent shortwave trough will slide northeast across the Plains
towards the Great Lakes Sunday and Monday supporting a surface low
to lift northeast  across the region. While medium range guidance
continues to exhibit differences with the track of this system
(greatly impacting precipitation type), the general pattern will
result in active weather for the end of the weekend and the start of
the new work week. Overall expect widespread precipitation to last
through Sunday and Monday (likely in the form of just rain), before
pulling east Monday night, changing rain over to snow as cold air
wraps in behind the exiting low. Additionally, there will be some
weak instability ahead of the system Sunday and Sunday night
supporting the slight chance for some rumbles of thunder.

In the wake of the passing system, surface high pressure will slide
east across the region Monday night into Wednesday. The next surface
low will then enter the Great Lakes region late Wednesday increasing
the chances for precipitation to enter back into the forecast.
-- End Changed Discussion --

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Fairly widespread snow showers are expected this afternoon,
roughly through 21Z for most TAF sites, and 23Z at KART. These
will produce brief periods of IFR or lower VSBY (1/2SM to 2SM)
and MVFR CIGS at our TAF sites. Snow showers taper from west to
east late this afternoon and early evening, with localized MVFR
flight conditions. High pressure builds in tonight, resulting in
clearing skies and widespread VFR flight conditions for most of
tonight and lasting through early Thursday afternoon.

Outlook...

Thursday afternoon and night...Mainly VFR. A chance of rain or
snow showers with MVFR flight conditions late Thursday
afternoon and Thursday evening.

Friday...Mainly VFR with a chance of rain/snow showers.

Saturday through Sunday...MVFR/IFR with periods of rain likely,
possibly mixed with snow across the eastern Lake Ontario region.

Monday...VFR/MVFR with rain showers likely.

&&

.MARINE...
Winds will increase on Lake Ontario this afternoon with the
passage of a cold front. Small Craft Advisories in place for
most of Lake Ontario through this evening. High pressure will
then build into the lower Great Lakes tonight, with diminishing
winds.

Another cold frontal passage will bring another uptick in winds
Thursday night, which may require a 6 to 9 hour period of Small
Craft headlines. This will be followed by another ridge of high
pressure late Thursday night and Friday.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 10 PM EDT this evening for LOZ042.
         Small Craft Advisory until 4 AM EDT Thursday for LOZ043-
         044.

&&

$$

SYNOPSIS...Apffel
NEAR TERM...Apffel
SHORT TERM...JM/JJR
LONG TERM...EAJ
AVIATION...Apffel
MARINE...Apffel