Forecast Discussion

Forecast Discussion for BUF NWS Office
000
FXUS61 KBUF 242002
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
402 PM EDT Sun Mar 24 2019

.SYNOPSIS...
A cold front with scattered rain and wet snow showers will move
through tonight. Temperatures will drop back below normal in the
wake of the front for Monday and Tuesday, then significant day to
day warming will take place during the remainder of the work week.

&&

.NEAR TERM /THROUGH MONDAY/...
A cold front will steadily march south through the region tonight,
reaching the Pennsylvania border by Monday morning. The cold front
will be marked by a period of scattered rain and wet snow showers
with a northerly wind shift. Best precipitation coverage should be
across the North country with some orographic interactions. Any snow
accumulations will be limited to less than a half inch over the
highest terrain. Precipitation will taper off fairly quickly behind
the front with skies also rapidly clearing, although some favored
northerly flow upslope areas may see some lingering cloudiness
Monday morning.

Strong high pressure and associated very dry air will take hold
for Monday. This will result in plenty of sunshine. Daytime
temperatures will be some 5 to 10 degrees below normal with most
highs in the mid and upper 30s.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
A large area of high pressure, and its associated dry airmass, will
cross the forecast region this period, cresting over the Eastern
Great Lakes Tuesday night. This feature will lower RH values to
around 25 - 30 percent inland midday Tuesday and Wednesday,
though wind speeds under the high pressure will generally be 15
mph or less.

Cool temperatures and a northerly wind will be found ahead of the
surface high pressure ridge axis, while a warming trend will
commence behind the surface high with a southerly flow ensuing.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Unfortunately, there is some bad news in the 12Z model guidance
which may impact the late week warm up. GFS/GGEM/ECMWF guidance are
stronger with a shortwave and associated cold front on Thursday, and
it now appears that this front will be strong enough to push across
(or into) our region late Thursday or Thursday night. Thursday
should still be warm and mainly dry, with a risk of some showers
late in the day with the approach of this boundary. After this, the
forecast gets very tricky since the front will loose its push from
the shortwave and stall somewhere near our region. This will lead to
a very sharp thermal gradient where daytime temperatures north of
the boundary will be in the 40s, and south of the boundary in the
60s. Given this uncertainty, the forecast hedges in the middle for
Friday, since it`s uncertain which side of the front the area will
be on. The stalled boundary will also maintain a risk of showers,
however these will be hit or miss leaving the majority of the day
dry.

On Friday night a broad upper level trough will exit east of the
Rockies, and this will interact with a northern branch shortwave
and lead to the development of a stretched surface low along
the stalled frontal boundary. As this low approaches, the
boundary is likely to lift northward some around Saturday. This
will maintain a chance of showers on Saturday, with again a wide
north to south range in temperatures expected. By Sunday, a
northerly flow will develop behind the weak surface low with
cooler temperatures moving in late in the weekend. Some guidance
is cold enough to support snow showers late Saturday night into
Sunday, but the spread in model guidance suggests below normal
forecast confidence for next weekend.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
VFR conditions will be in place across the region into this evening,
despite thickening high and mid level cloud cover. Gusty surface
winds to around 25 knots across the Niagara Frontier (KBUF/KIAG)
will subside after 23z. Conditions will deteriorate tonight as a
cold front pushes south across the region. While only scattered
light rain and wet snow showers are anticipated with the frontal
passage, ceilings are expected to lower to low end VFR or MVFR
levels. There may even be some local IFR ceilings for the
higher terrain of the Finger Lakes and Southern Tier.

Outlook...
Monday...VFR...except for some lingering MVFR cigs early.
Tuesday through Thursday...VFR.
Thursday night and Friday...VFR/MVFR. A chance of showers.

&&

.MARINE...
The surface pressure gradient ahead of an approaching cold front
will be just strong enough to support gusty southwest winds on the
eastern end of Lake Erie. This will maintain small craft conditions
through the rest of the afternoon.

A cold front will march southward across the region tonight. This
will result in a shift to northerly winds that could produce a few
hours of choppy water for the Lake Ontario nearshore waters west of
Oswego.

Winds are likely to continue to increase on Lake Ontario during the
course of Monday, possibly leading to another round of small craft
advisories.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for LEZ020-
         040-041.

&&

$$

SYNOPSIS...RSH/TMA
NEAR TERM...RSH/TMA
SHORT TERM...Thomas
LONG TERM...Apffel
AVIATION...RSH/TMA
MARINE...RSH/TMA

NWS BUF Office Area Forecast Discussion