167
FXUS61 KBUF 190713
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
313 AM EDT Sun May 19 2024

.SYNOPSIS...
High pressure extending from the Labrador Sea and the Canadian
maritimes back across our region will generally keep fair dry
weather in place through at least the beginning of the new work
week. More notable will be the summer like heat that we can look
forward to, as the mercury in most areas will climb WELL into the
80s for the Monday through Wednesday timeframe.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
While fair dry weather will be in place throughout the region
overnight, as was expected lingering low level moisture is
encouraging fog development, especially across areas west of the
Genesee Valley. Expansion of the fog can be seen quite nicely on
Nighttime Microphysics satellite. It will stay on the mild side of
average with lows mainly in the mid and upper 50s.

After early morning fog and stratus dissipate, mainly dry weather is
expected Sunday as a mid and upper level ridge starts to build
overhead. There will be an outside chance for some diurnally driven
scattered showers across the Genesee Valley/Finger Lakes with a weak
lingering surface convergent boundary in place. High temperatures
should peak in the mid to upper 70s.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
A mid and upper level ridge will become anchored over our region
this period, with mainly fair weather and building warmth.

A shortwave trough will ripple through this ridge over Canada Monday
night, possibly bringing a shower down into the Saint Lawrence
Valley. Otherwise moisture left behind this shortwave may aid in
development of a few spot showers or thunderstorms along a
strengthening lake breeze boundary Tuesday afternoon. Subsidence
with the ridge aloft should keep any activity isolated.

The southwesterly flow will steadily increase temperatures aloft at
850 hPa, such that at the surface most areas will see day to day
warming of a degree or two. By Tuesday, 850 hPa temperatures of +14
to +16 will yield widespread 80s, and perhaps a few 90 degree
readings in the Genesee Valley. The exception will be northeast of
Lakes Erie and Ontario where the southwest flow off the cool Lake
waters will hold back the heat for metro areas of Buffalo and
northern Watertown.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Low pressure tracking from Lake Superior to Hudson Bay will place
our region in the warm sector for much of the day Wednesday. With
SSW downslope flow will hedge on the warm side of guidance with
highs 85 to 90 across lower elevations, including Buffalo and
Rochester. 12Z model consensus brings a cold front through Thursday
evening, with a chance of showers and thunderstorms ahead of the
front Wednesday afternoon and showers and thunderstorms likely
Wednesday night with the frontal passage.

Possibly a lingering shower behind the front on Thursday with
afternoon temperatures still slightly above normal despite the cold
frontal passage. After this, weak high pressure will build across
the region resulting in mainly rain-free weather Thursday night
through Friday night. A secondary cold front will approach the
region Thursday night, and may pass through all or part of the area
Friday and into the weekend. Lower confidence in temperature
forecast for this time period, with forecast highs in the mid 60s to
mid 70s representing a consensus of model guidance. These could be 5
or more degrees warmer or cooler depending on the position of the
front. Chances of showers with the front will remain low, but a
stray shower can`t be ruled out on Saturday.

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
VFR conditions expected east of Lake Ontario (KART) right through
Sunday with solid mid level decks remaining in place through the
remainder of the overnight. Meanwhile conditions deteriorate from
east to west south of Lake Ontario, with the worst conditions
(VLIFR/LIFR) across the Niagara Frontier (KBUF/KIAG) and far
southwestern NYS (KJHW) where VSBYs have fallen to a quarter mile
over the past 1 to 2 hours. Nighttime Microphysics satellite shows
the denser fog expanding inland from the western Lake Ontario and
eastern Lake Erie shorelines. Lower Genesee Valley will likely be in
between VFR to the east and VLIFR to the west, so the battle at KROC
will be between the formation of fog versus stratus.

Heading into Sunday, low stratus and fog over western NY will slowly
improve to VFR through the mid to late morning hours. Widespread VFR
conditions then expected for Sunday afternoon and evening, although
there may be a stray shower or rumble of thunder toward the upper
Genesee Valley during the afternoon.

Outlook...
Monday and Tuesday...mainly VFR.
Wednesday...VFR/MVFR. Showers and thunderstorms likely.
Thursday...Mainly VFR. A chance of showers and thunderstorms.

&&

.MARINE...
A highly saturated air mass will continue over the lower Great Lakes
tonight allowing for fog and stratus to expand over the Lakes with
poor visibility conditions possibly becoming widespread late tonight
into the first half of Sunday on Lake Erie and the western end of
Lake Ontario with light flow.

Otherwise, light winds with minimal wave action expected on the
lakes through Monday.

South winds develop and begin to pick up by Tuesday as a cold front
near the eastern Great Lakes but conditions will likely remain below
small craft levels. The next chance at small craft conditions may
materialize by midweek as low pressure sends a cold front through
the Lakes.

&&

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

&&

$$

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