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084
FXUS61 KBUF 200935
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
535 AM EDT Thu Jun 20 2024

.SYNOPSIS...
Muggy and hot again today with showers and thunderstorms, some of
which could produce strong gusty winds and torrential downpours.
While temperatures will begin to moderate beginning Friday, real
relief likely won`t come until the beginning of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
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Remnant MCV rolling through the northern part of the Niagara Frontier
with heavy rain and lightning this morning. This complex of storms
has weakened considerably from overnight with GOES-16 IR showing
cloud tops warming. That said...will continue to keep an eye on it
as convection could flair up again as it rolls ENE.

Otherwise...very muggy conditions (dwpts in the 60s to low 70s) this
morning. Temps as of 09Z are in the 70s across the area.

Hot and muggy again today, all heat related advisory will remain in
place for the entire forecast area. That said...the H598 ridge
centered to our south will begin to sink southward and then become
east to west oriented by Friday. We should see some cooling aloft
today, with H850 shaving off a few degrees. This may be reflected in
daytime temperatures of a degree or two.

As the ridge shifts position today, we should see more widespread
convection inland from the lakes. Given PW values of 1.6-1.8 inches,
weak flow, and small MBE vectors there will be the potential for
flash flooding. This will especially be the case where storms have
already moved over from previous convection this week. While 0-6km
shear isn`t all that impressive (20 knots), any stronger cells will
also have the potential to produce damaging winds and some hail.

Summing it all up...SPC has placed our forecast area in a MRGL/SLGT
risk for SVR weather today, and a MRGL risk for excessive rainfall.

Convection will linger into a portion of the night but with the loss
of daytime heating coverage will likely decrease. Another muggy and
mild night will be on-tap with lows only in the 60s to low 70s.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
Friday, the frontal boundary will stall over the forecast area
and continue to provide the opportunity for showers and
thunderstorms with the best chance for showers toward the NY/PA
line. High temperatures on Friday will be in the low 80s to near
90, on the northern side of the frontal boundary. If the front
stalls farther north, then temperatures will be a bit warmer.

Warmer and more humid conditions return for the weekend as warm
front moves north of the forecast area.

Friday night, the stalled front across the area will begin to slowly
push north as a warm front late in the night and into the early
Saturday morning. There should be a break in the shower/storm
activity, especially with the lack of diurnal processes.
Showers/storms potential will then increase around daybreak Saturday
as the front starts moving colliding with a ribbon of vorticity and
area of increased moisture pushing towards the region. As of now,
the best chance for showers early Saturday morning looks like it
will lie across the North Country. Certainly can`t rule out a shower
or storm for the rest of the area as the warmth and humidity build
back into the region.

Showers will expand in coverage across the entire area throughout
the day Saturday as daytime heating increases, and as the sfc low
(and its moisture) approaches the region. With the frontal boundary
orientated from west to east, just to the north of Lake Ontario and
into the North Country, the best chances for showers and storms will
be lie along the front. Afternoon high temperatures will warm to the
low 80s to low 90s across the area, with the cooler temperatures
expected across the North Country with the warm front over/near the
area.

The warm sector of the surface low to the north will be firmly in
place for Saturday night continuing the potential for showers/storms
across the entire area.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
With the warm sector of the surface low to the north still in place
for Sunday, showers/storms will continue across the entire area.
Showers will then increase from northwest to southeast across the
area heading into the afternoon as a cold front approaches from the
west. Warm and humid conditions will continue through Sunday as the
warm sector remains in place ahead of the cold front.

The aforementioned cold front associated with the surface low
passing to the north will cross the area on Sunday evening and
overnight, causing more organized showers/storms to move through the
area. A potent shortwave trough tracking across the area behind the
passing front will continue the shower potential for Monday.

Increased ridging and an incoming surface high will result in drier
conditions for Monday night through most of the rest of the period,
though some guidance does bring some showers back into the region
for mid-week.

Temperatures will be well above normal for Sunday with highs in the
low 80s to near 90. Temperatures cool behind the passing cold front
to the mid 70s to low 80s for Monday before warming again for
Tuesday & Wednesday back to the low to upper 80s.

&&

.AVIATION /10Z THURSDAY THROUGH MONDAY/...
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Lingering showers and thunderstorms will bring brief localized MVFR-
IFR this morning. There will also be some fog in the river valleys
across the S. Tier which will impact KJHW through 12Z.

Otherwise...mainly VFR at area terminals. Areal coverage of showers
and storms will be greater today, with a risk of very heavy rain and
gusty winds.

Tonight...VFR conditions outside of showers and storms. Once again
there will be the potential for some fog in the river valleys of the
S. Tier.

Outlook...
Friday and Saturday...Mainly VFR, but a chance for mainly
afternoon and evening thunderstorms inland from the lakes.
Sunday...VFR/MVFR. Showers and thunderstorms likely.
Monday...Mainly VFR, but a chance for afternoon and evening
thunderstorms inland from the lakes.
-- End Changed Discussion --

&&

.MARINE...
A generally quiet period is expected for the lower Great Lakes
through the rest of the week and into the weekend as a large
upper-level ridge remains across the eastern CONUS, resulting
in a lighter surface flow. Only concern will be in the afternoon and
early evening hours as showers and thunderstorms could produce
higher wind gusts and waves.

&&

.CLIMATE...
The heat will continue today. Below are record high
temperatures for our three main climate sites:

...Buffalo...

...Date.....Record Maximum (F)...Record warm Minimum (F)...

...June 20........92/1995............73/2012


...Rochester...

...Date.....Record Maximum (F)...Record warm Minimum (F)...

...June 20........95/1953............72/1923


...Watertown...

...Date.....Record Maximum (F)...Record warm Minimum (F)...

...June 20........90/1971............71/2012

Temperature records for Buffalo and Rochester date back to 1871.
Temperature records for Watertown date back to 1949.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Heat Advisory until 8 PM EDT this evening for NYZ001>008-
     010>014-019>021-085.
MARINE...None.

&&

$$

SYNOPSIS...AR
NEAR TERM...AR
SHORT TERM...EAJ/SW
LONG TERM...EAJ/SW
AVIATION...AR
MARINE...AR
CLIMATE...Thomas/TMA