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669
FXUS61 KBUF 132358
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
758 PM EDT Thu Jun 13 2024

.SYNOPSIS...
A cold front will slowly sag through the region tonight while likely
generating some showers and possible thunderstorms into Friday
morning. A fresh Canadian airmass and expansive high pressure in its
wake will guarantee fair but cool weather to start the weekend...and
this will be followed up by simply gorgeous weather on Sunday. Mid
summer heat and humidity will then build across our region for much
of next week with apparent temperatures in  most areas soaring to
between 95 and 100.

&&

.NEAR TERM /THROUGH FRIDAY NIGHT/...
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A cold front over the Upper Great Lakes will slowly settle to
the south during the course of the night...crossing our forecast
area between midnight and early Friday morning. The front will
generate some showers and possible thunderstorms in the process.
While the timing of the cold frontal passage will not be
conducive to support strong convection...we can expect basin
average rainfall amounts that will range from a tenth to a
quarter inch. Any organized convection will have the potential
to produce localized amounts of a half to up to one inch.

Some leftover showers will be possible Friday morning...mainly south
of Buffalo and Rochester...as the aforementioned cold front will
continue its slow push into Pennsylvania. Clearing skies from north
to south will then take place during the midday and afternoon. This
should leave pleasant conditions for most areas for the latter
portion of the day. It will be cooler with max temperatures in the
70s.

Expansive high pressure over the Upper Great Lakes Friday evening
will slowly drift southeast during the course of the overnight. This
will guarantee fair dry weather with temperatures falling into the
50s.
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&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Broad mid-level ridging centered across the Central Plains Saturday
morning will shift east into the northern Great Lakes Sunday.
Meanwhile to the east, the mid-level trough centered over New York
State Saturday will give way to the Atlantic coastline. At the
surface, a broad area of high pressure will slide across the lower
Great Lakes supporting dry weather throughout the weekend.

With no real weather to speak of, the temperatures will be the focus
of the forecast for the foreseeable future. With the exiting trough
aloft, the last breath of cooler air will arrive for Saturday as
temperatures at 850mb dip down toward 7-8 degree Celsius. Highs
Saturday will range in the upper 60s to low 70s. As the ridge enters
the Great Lakes, temperatures aloft will begin to modulate
supporting highs to warm up into the low to mid 70s across the North
Country and the upper 70s to low 80s elsewhere.

Overall this weekend will be a great one to spend outdoors!

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
...Headline Worthy Summer Heat Expected This Period...

A prolonged period of heat and higher humidity will arrive next
week as a ridge of high pressure builds across the eastern
Great Lakes region. 500mb heights will climatologically be in
the 99th percentile for this time of year and even reach maximum
values for all hours over the Mid-Atlantic and southern New
England Wednesday through Thursday. A southerly flow will
transport a warm and moist airmass into the forecast area. Over
the course of the work week, the ridge will build north across
the eastern U.S. which opens the door for the potential for
"ridge riders" or clusters of thunderstorms to potentially
impact the region Monday through Tuesday. There is high
uncertainity that this will materilize but the pattern suggests
is a possibility. The ridge will then be centered overhead
Wednesday through Thursday which will lessen chances for
convective systems across the region.

Speaking on precipitation chances, dewpoints will climb to the upper
60s to low 70s through the work week. Surface based instability will
be on the rise during the day which may drive convection outside of
common lake shadows. There is a slightly higher chance of showers
and thunderstorms Monday afternoon and Tuesday afternoon than
Wednesday and Thursday.

In terms of sensible weather, this will translate to a prolonged
stretch of oppressive summer heat and humidity. Daytime temperatures
Monday will feature widespread upper 80s and lower 90s, though
remaining a bit cooler across the North Country with low and mid 80s
where a slightly cooler airmass will linger. By Tuesday and
Wednesday, widespread high temperatures in the low to mid 90s are
expected, hottest in the interior valleys and coolest just northeast
of both lakes (including the Buffalo area) as a persistent southwest
flow advects cooler marine air off the lakes. This heat comes as
dewpoints climb into the low 70s, which will cause overall heat
indicies in the afternoon to climb into the mid 90s to lower 100s.
Daytime highs average the upper 70s for Buffalo, Rochester, and
Watertown during the days of June 17-20.

It will not only be the impressive level of oppressive midday and
afternoon heat to contend with, but the cumulative impacts of only
having the mercury settle to near 70 for the overnights (Monday
night and beyond), thereby extremely limiting any relief.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
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VFR conditions will be in place through this evening.

A slow moving cold front will press through the region later tonight
and early Friday. While VFR flight rules are forecast to persist...
the front will support at least scattered shower and thunderstorm
activity. The exception will be across the Southern Tier where MVFR
to IFR cigs will be likely between about daybreak and midday Friday.

Outlook...

Friday night through Tuesday...VFR.
-- End Changed Discussion --

&&

.MARINE...
A cold front will move across the lower Great Lakes late tonight and
early Friday. Southwest winds will increase ahead of the front, with
winds remaining elevated through Friday. This will bring choppy
conditions to both lakes. High pressure will then build back across
the waters with light winds and generally favorable boating
conditions during the weekend.

&&

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

&&

$$

SYNOPSIS...RSH
NEAR TERM...AR/RSH
SHORT TERM...EAJ
LONG TERM...HSK/PP/RSH
AVIATION...AR/RSH
MARINE...AR/RSH/TMA