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FXUS61 KBUF 161907
AFDBUF

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

.SYNOPSIS...
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.

&&

.NEAR TERM /THROUGH MONDAY/...
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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.

Following the warm frontal passage temperatures on Monday will
be notably warmer, and it will also be more humid. Apparent
temperatures will rise into the upper 90s in the lower Genesee
Valley and Western Finger lakes region, where a Heat Advisory
was issued starting Monday. Elsewhere, will be hot with high
temperatures in the upper 80s and apparent temperatures in the
lower 90s.

For the most part, the day should be rain-free but some high res
models do develop some isolated thunderstorms in the afternoon.
Given forecast soundings, it appears this is likely overdone and
only supports a slight chance PoPs.
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&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
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...Dangerous Heat Wave Will Begin For The Region...

Surface high pressure will be anchored over the Atlantic and a deep
southerly flow will bring HOT and HUMID conditions during the day
and WARM and HUMID conditions during the night Monday night through
Wednesday night.

An anomalously strong upper level ridge will build across the
eastern Great Lakes region and Northeast through mid-week. Warm air
advection will take place Monday night through Tuesday with 850mb
temperatures climbing to +20C. Very warm Monday night with lows in
the upper 60s across the higher terrain and low 70s across the lake
plains. Temperatures will soar into the low 90s across the region
with valley locations reaching the mid to upper 90s Tuesday.
Dewpoints will climb into the upper 60s to low 70s with PWAT values
1.5 inches or greater. The combination of the heat and humidity will
drive heat index values into the upper 90s to low 100s Tuesday
afternoon. The forecast area will be on the northwest side of the
strong upper level ridge and should be enough in the ridge to keep
any upstream thunderstorm complexes outside the forecast area
Tuesday. There will be high surface based instability across the
region (sans the immediately shorelines.) Terrain circulations and
lake breeze boundaries will likely produce a cu field with isolated
to scattered showers and thunderstorms. Any convection will wane
into the evening hours. The very warm airmass will persist through
Tuesday night with overnight lows only reaching the low 70s.

There is little change in the sensible weather for Wednesday and
Wednesday night. Another HOT and HUMID day with highs in the low to
mid 90s, dewpoints in the upper 60s to low 70s, and heat index
values in the upper 90s to low 100s. There is some model guidance
that shows 850mb temperatures a few degrees higher (EC) which could
add a degree or two to high temps Wednesday. The forecast area will
remain on the northwest side of the upper level ridge Wednesday
through Wednesday night. The convective potential is similar to
Tuesday with low coverage of showers and thunderstorms. Another very
warm night with lows in the low to mid 70s.

A Heat Advisory is in effect for the entire forecast area
Tuesday through Thursday.
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&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...

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The heat and humidity will be the big story this period. Highs in
the 90s Thursday combined with dewpoints in the 60s and lower
70s will bring apparent temperatures into the 90s to lower 100s.

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

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
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.

&&

.MARINE...
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.

&&

.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...
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NY...Heat Advisory from noon Tuesday to 8 PM EDT Thursday for
     NYZ001-002-006>008-010>012-019>021-085.
     Heat Advisory from noon Monday to 8 PM EDT Thursday for
     NYZ003>005-013-014.
MARINE...None.
-- End Changed Discussion --

&&

$$

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