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FXUS61 KBUF 161742
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
142 PM EDT Sun Jun 16 2024

.SYNOPSIS...
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High pressure sliding off the New England coast will maintain
dry weather through this evening. This will also bring in warmer
weather, which will last through at least Thursday. It will be
dangerously hot, with apparent temperatures likely to reach 100
at some locations Tuesday and Wednesday.
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&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
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Surface high pressure will drift east off the New England coast,
and this combined with mid-level ridging will maintain rain-free
weather. A patch of high clouds will move across the area this
afternoon, but will only temporarily filter sunshine. Today will
also start the warming trend, with afternoon temperatures
reaching the lower to mid 80s across far western New York and
the Genesee Valley, with a range of 70s further east.

A warm frontal segment will pass by to our north, and this will
begin to bring in a more humid air mass. This frontal passage
will also bring a small chance of showers, mainly across the
Eastern Lake Ontario region late tonight.
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&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
...Dangerous Heat Wave Will Begin to Impact the Region...

A 500 hPa ridge will expand this period, after a shortwave rounds
the top of the ridge axis Monday morning. There may be a few
lingering showers east of Lake Ontario Monday morning, otherwise a
dry day is expected, with building heat and humidity.

Monday the surface pressure gradient will increase with the passing
of the shortwave aloft, with a bit of a southerly breeze in the 20
mph range. While not a great magnitude, this southwesterly flow
behind the departed surface high will increase moisture advection
through the day.

Temperatures Monday will climb into the 80s, and lower 90s for the
lake Plain and Genesee Valley. The southwest breeze may be strong
enough to keep Metro Buffalo and Watertown in the upper 80s. As the
dewpoints increase with the moisture advection through the 60s
Monday heat index values will climb well into the 90s.

Southerly flow will maintain a muggy and warm night, with lows only
in the upper 60s interior WNY, to lower 70s across the Lake Plain,
Genesee Valley and much of the North Country.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
...Dangerous Heat Wave Will Continue For The Region...

A nearly 600 dm 500 hPa ridge, centered just to our east and south
Wednesday will maintain both summer`s intense heat and humidity over
our region Tuesday through at least Thursday. This feature will
slowly slide southward through this period, with a zonal flow aloft
by period`s closure.

Under this ridge, subsidence will prevent all but a few of the
strongest updrafts from forming into showers and thunderstorms
Tuesday through Thursday, with just isolated convection along a lake
breeze boundary across WNY. Subtle shortwaves within the zonal flow
aloft Friday and Saturday may trigger a bit more convection,
especially near Lake Ontario and points eastward.

The heat and humidity will be the big story this period. Highs in
the 90s Tuesday through Thursday combined with dewpoints in the 60s
and lower 70s will bring apparent temperatures into the 90s to lower
100s. Highest heat index values will be along the southern shoreline
of Lake Ontario and within the Genesee Valley. Overnight lows will
be in the 70s with mugginess continuing. Winds will be light, with
even Buffalo and Watertown able to reach into the 90s without the
cooling lake breeze. With such hot conditions, please remember to
drink plenty of fluids, stay in cooler areas (air conditioned or
shaded), and wear light loose clothing to help remain cool and avoid
heat illness!

There will be potential for both record maximum and minimum values
this period, with more information in the climate section below.

Under the zonal flow later in the period daytime highs will drop
back several degrees, with less 90s found Friday and Saturday.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
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VFR flight conditions will prevail through Monday afternoon.
There`s a small chance of showers east of Lake Ontario late
tonight, otherwise just periodic cloud cover with cloud bases
well in the VFR flight category.

Outlook...

Monday night...VFR.
Tuesday through Friday...VFR, but a slight chance for afternoon
thunderstorms inland from the lakes.
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&&

.MARINE...
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Lake breeze enhanced easterly winds will increase this afternoon,
especially on the central and western portions of Lake Ontario
where some choppy conditions may develop.

Winds will then be generally light Monday through much of next week
as high pressure anchors over the Ohio Valley and New England.
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&&

.CLIMATE...
A prolonged period of heat is expected for our region, starting
Monday June 17th. Below are record high temperatures for our three
main climate sites:

...Buffalo...

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

...June 17........94/1994............73/2006
...June 18........95/1994............73/2006
...June 19........90/2001............73/1919
...June 20........92/1995............73/2012


...Rochester...

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

...June 17........94/1994............70/1994
...June 18........97/1957............72/2018
...June 19........95/2001............72/1919
...June 20........95/1953............72/1923


...Watertown...

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

...June 17........89/1994............68/1949
...June 18........91/1957............70/1992
...June 19........91/2007............70/1949
...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...None.
MARINE...None.

&&

$$

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