483
FXUS61 KBUF 130807
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
407 AM EDT Mon May 13 2024

.SYNOPSIS...
A warm front will move across the area today with a few periods of
showers and possibly a thunderstorm or two. This front will usher in
a period warm and unsettled weather which will last through the
middle of the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Regional radar shows an area of showers approaching western NY
this morning. Weak echos across the Finger Lakes region this
morning may result in some sprinkles through daybreak.

A mid-level ridge will flatten across the forecast area today. A
cold front extends from low pressure over James Bay to Lower
Michigan this morning. A warm front coincides with a nose of a 40kt
low-level jet across eastern Michigan/southern Ontario. Showers with
a few embedded thunderstorms will move into western NY this morning.
Hi-res guidance shows a higher chance of showers across the northern
tier of western NY with a low chance closer to the Pennsylvania
border. This area of showers will move into central and north
central NY through midday. Daytime heating will increase surface
instability behind the warm front and additional showers and a few
thunderstorms will develop across western NY this afternoon. The
warm front will move northward and showers and any thunderstorms
will move into north central NY late this afternoon into this
evening.

The pressure gradient will tighten across the area today and
southerly winds will become breezy especially across the Niagara
Frontier. Overall, south winds will average 10 to 20 mph. Gusts up
to 35 mph are possible across the Niagara Frontier with lesser
magnitude elsewhere. Warm today with highs in the low to mid 70s
across western NY to the mid to upper 60s east of Lake Ontario.
Temperatures may reach the upper 70s along the Lake Erie shoreline,
south of Buffalo.

The warm front will lift north tonight and showers will taper off
across the Saint Lawrence Valley overnight. Mostly dry conditions
are expected for most of the night, however shower chances begin to
increase across far western NY late tonight ahead of the approaching
cold front. Lows will fall to the mid to upper 50s tonight.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Nearly stationary frontal boundary located in the vicinity of Lake
Ontario to the Saint Lawrence River Tuesday morning. This frontal
boundary will be the focal point for shower and thunderstorm chances
Tuesday, as it sags slowly southward into the region during the day
with the vast majority of the guidance having the boundary bisecting
the area by the end of the day. Precipitable water values nearing
1.25" not too far above climatological normals, but given the
relative small shear vectors and an enhanced theta-e environment the
potential exists for repeated rainfall which could be heavy at times
with any convective activity.

The frontal boundary will continue to drift to the south Tuesday
night and Wednesday in response to the building high pressure system
over Ontario. Precipitation chances, though lowering during this
period will continue through Wednesday, before high pressure fills
in across the Great Lakes.

There could still be some lingering light showers Wednesday evening,
but the overall trend will be fro continued drying with most of
Wednesday night winding up being dry.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
A progressive flow aloft will maintain chances for showers and
thunderstorms this period. Thursday may end up dry, with low PWATS
and a narrow ridge of high pressure nearby...this between an east
coast low, and trough across the Plains. However there is a
possibility that a few showers from the east coast low sneak far
enough westward into our eastern CWA.

This western trough will push eastward, likely in the Friday to
Saturday timeframe...with still a good deal of model spread to
narrow down it`s passage. Behind the trough lowering chances for
precipitation, through a secondary trough dropping out of Canada may
bring chances for showers to the North Country. Temperatures will
average above normal, especially Friday ahead of the trough, and
again on Sunday when a milder airmass begins to push northward.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
VFR conditions are across the eastern Great Lakes region this
morning. An area of mid-level clouds extends north-south across
western NY and will continue to move east this morning. Regional
radar shows showers just west of western NY with some weak echoes
across the Finger Lakes region. Clearing and calm winds across far
western NY may produce a brief period of MVFR/IFR at KJHW. A
westerly low-level jet will strengthen across the region this
morning. There will be a brief period of low-level wind shear prior
to surface winds increasing this morning.

A warm front will move across the region this afternoon. Showers
will track across western NY this morning and east of Lake Ontario
this afternoon. Another round of showers will develop across western
NY behind the warm front this afternoon. A few thunderstorms can`t
be ruled out and this activity will move northward into north
central NY late this afternoon into this evening. VFR conditions
will continue today, however low-end VFR will move into KART this
afternoon. Any heavier showers or thunderstorms could produce a
brief period of IFR but confidence is low of reaching a TAF site.

Outlook...

Tuesday...MVFR/IFR with the likelihood for showers and thunderstorms.
Wednesday...MVFR/IFR with showers, especially for southern and eastern
portions of the area. Improving later Wednesday.
Thursday...VFR.
Friday...VFR. A chance of showers late.

&&

.MARINE...
Southwesterly winds will increase following the passage of a warm
front today. Winds and waves will likely stay below Small Craft
Advisory criteria, although it will become choppy at times.
Otherwise, winds and waves are expected to remain well below Small
Craft conditions with just some light chop at times through at least
Tuesday.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.

&&

$$

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