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832
FXUS61 KBUF 141040
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
640 AM EDT Fri Jun 14 2024

.SYNOPSIS...
A cold front will continue to sag through the region this morning
bringing some showers and a few thunderstorms. A fresh Canadian
airmass and expansive high pressure behind the front will guarantee
fair and cooler weather this weekend. Mid summer heat and humidity
will then build across our region for much of next week with
apparent temperatures in most areas into the mid 90s to around 100.

&&

.NEAR TERM /THROUGH TONIGHT/...
Cold front continuing to make its way into the region early this
morning. Broken band of weakening convection along the front will
move south through the area this morning. Current radar imagery
suggesting that overall coverage will be quite scattered in nature
any many locations will remain dry. Frontal boundary drops south of
the region by mid to late morning with clearing skies behind it
through the remainder of the day. It will be cooler today with high
temperatures a solid 10 degrees cooler than Thursday with highs in
the 70s.

Expansive high pressure over the upper Great Lakes this evening will
slowly drift southeast during the course of tonight. This will
guarantee fair dry weather with temperatures falling into the 50s.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Superb weather for the weekend as upper level troughing quickly
shuffles eastward Saturday, allowing an expansive ridge of high
pressure to build over the Great Lakes. This will keep the area dry,
and outside of a few passing mid/high clouds Sunday, under mostly
clear skies.

Temperatures Saturday will initially be on the `cool` side for June
behind the trough, which will translate to comfortable highs in the
upper 60s and low 70s. As the surface ridge crests east of the
region Sunday and moves off the East Coast by Sunday night, temps
will get a boost into the mid/upper 70s, likely a few readings in
the 80s across far western NY. Lows Saturday night will be rather
chilly with a range of 40s across the interior and low 50s closer to
the lakes. Warmer for Sunday night with a range of 60s across the
region, possibly near 70 close to the Lake Erie shoreline.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
...Heat Wave To Impact The Region Next Week...

A very strong 500mb ridge will anchor itself across much of the
eastern CONUS and western Atlantic through much of the week, which
will dominate the sensible weather across the eastern Great Lakes.
NAEFS ensemble guidance continues to indicate this ridge will be of
anomalous strength with 500mb heights in the 99th percentile, if not
exceeding the maximum climatological values for the Northeast for
nearly the whole week. Latest runs of the deterministic ECMWF in
particular continue to forecast overhead 500mb heights reaching
600dam, with coincident 850H temps near +24C at times. Deep
anticyclonic flow around the resultant Bermuda High will cause hot,
humid air to surge across the eastern CONUS. Given the strong signal
from nearly all available long range guidance packages, confidence
is high in a prolonged stretch of oppressive summer heat and
humidity lasting through much of the week.

Forecast thinking has not changed much from previous updates in
regards to expected temps and heat indices next week. Daytime highs
Monday will feature widespread upper 80s and lower 90s, remaining a
bit cooler across the North Country in the upper 70s to mid 80s as
slightly cooler airmass initially lingers in the region. By Tuesday
and Wednesday, widespread high temperatures in the low to mid 90s
are expected. Highest temps will be in the interior valleys, while
cooler temps will be found 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. Temps are expected to be a
few degrees lower on Thursday, back down into the upper 80s and low
90s. For context, daytime highs average the upper 70s for Buffalo,
Rochester, and Watertown during the days of June 17-21.

Even though heat indices will peak in the afternoon hours each day
next week, nighttime will offer very little (if any) relief. Low
temperatures from Monday night onwards are expected to only be in
the low to mid 70s, with high humidity likely making for VERY muggy
sleeping weather.

Otherwise...The primary forecast uncertainty through much of next
week continues to be on convective potential. Guidance continues to
indicate a series of "ridge rider" showers and storms periodically
cresting over the ridge and into the eastern Great Lakes region, the
first batch of which could potentially arrive as early as Monday
night. In addition, with dewpoints climbing into the upper 60s and
low 70s, daytime surface based instability will likely be present
each afternoon...Though the strong ridge should preclude much of the
diurnal convective potential with strong capping expected to be in
place. Given the low confidence in shower and storm timing and
coverage, PoPs values remain on the low side (15-30%) through
Thursday.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
A slow moving cold front will continue to press through the region
this morning. While VFR conditions will persist, the front will
support scattered shower and thunderstorm activity. A brief drop to
MVFR is possible in the showers/storms.

Shower and thunderstorm activity will diminish behind the cold front
by late morning. Widespread VFR with only some diurnal cumulus and
sct-bkn mid level clouds the the rest of the day.

Outlook...

Tonight through Tuesday...VFR.

&&

.MARINE...
A cold front will move across the lower Great Lakes through this
morning. Westerly winds behind the front should remain below 15
knots today, before becoming more northerly and weakening
tonight. High pressure will 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/TMA
NEAR TERM...AR/RSH/TMA
SHORT TERM...PP
LONG TERM...PP
AVIATION...AR/RSH/TMA
MARINE...AR/RSH/TMA