533
FXUS61 KBUF 301453
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
1053 AM EDT Sun Jun 30 2024

.SYNOPSIS...
A cold front will push through the region this morning...and this
will usher in a notably less humid airmass that we can enjoy through
the state of the new work week. While there will be some leftover
showers and possible thunderstorms around today...the weather will
be appreciably nicer than that from Saturday. High pressure over the
Upper Mississippi valley today will then build across the region for
Monday and Tuesday. This will guarantee near perfect weather to
start the week.

&&

.NEAR TERM /THROUGH MONDAY/...
A cold front as of 15z is working through WNY with a notable Td
drop in its wake from the 60s into the 50s. A few shower are
moving southeast ahead of this feature but most locales are
seeing dry weather.

Otherwise...breezy conditions with an increasingly COMFORTABLE
airmass today. Strong cold advection behind the front will actually
cause mercury levels to DROP during the course of the
afternoon...something that is quite unusual during the warm
season...let alone for the end of June when the sun angle/intensity
is at its peak.

A secondary cold front will push south through our region tonight. This
will combine with a northerly upslope flow across a relatively warm
Lake Ontario to generate a fair amount of cloud cover across our
region...along with scattered nuisance showers east of Lake Ontario.

The pain of the unsettled weather for much of the weekend will give way
to absolutely gorgeous weather on Monday...as expansive high pressure
over the Upper Great Lakes in the morning will make its way across our
region during the afternoon and evening. Max temperatures Monday will
be within a few degrees of 70 with low humidity and wall to wall
sunshine.

&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
Sprawling Canadian high pressure will build directly across our
region Monday night before slowly making its way to the mid-Atlantic
coastline on Tuesday...while low-amplitude upper level ridging
builds in aloft. This will provide us with continued fair dry
weather for this 24-hour period...with mainly clear skies Monday
night giving way to some increase in some high clouds Tuesday.
With respect to temperatures...ideal conditions for radiational
cooling will allow Monday night`s lows to range from the mid-
upper 40s across the interior of the Southern Tier/North Country
to the lower to mid 50s elsewhere...then a developing southerly
return flow around the backside of the surface high will allow
highs to climb back into the upper 70s to lower 80s on Tuesday.
Meanwhile humidity levels will remain comfortable...with surface
dewpoints only inching up into the mid to upper 50s by later
Tuesday.

Tuesday night the surface ridge will slip a little further
offshore...while the next mid/upper level trough and surface low
pivots across Manitoba and Ontario Provinces. With our region firmly
embedded within the deepening/strengthening southerly flow in
between these two systems...it will be a much warmer night than the
preceding two...with readings generally ranging through the 60s.
Meanwhile humidity levels will remain tolerable...as surface Td`s
will linger in the mid to upper 50s.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Wednesday and Thursday the aforementioned trough and surface low
will continue to make their way to northeastern Quebec and
Labrador...and in the process will ease a weak trailing cool front
across our area Wednesday night and early Thursday.

Out ahead of this boundary heat will build on Wednesday...with 850
mb temps surging into the mid to upper teens...thereby supporting
highs climbing back to the 85-90 range in many areas. Humidity
levels will also be on the increase...with surface dewpoints
climbing into the mid-upper 60s and lending an increasingly muggy
feel to the afternoon. As the cool front impinges upon this sultry
airmass later Wednesday afternoon and evening...it will bring about
an increasing likelihood for convection...with this especially the
case during the late afternoon and evening hours. With continued
good model agreement on this scenario have bumped PoPs up a little
more from continuity...with this round of showers and storms still
appearing likely to pose a problem for any fireworks displays
scheduled for Wednesday evening.

Convection should then tend to diminish in coverage from northwest
to southeast later Wednesday night and Thursday as the passing cool
front slips off to our south and ushers in a slightly cooler and
less humid airmass...though still cannot completely rule out some
spottier showers and storms lingering into Thursday afternoon near
the NY/PA border. Otherwise slightly cooler highs in the lower to
mid 80s are expected for Independence Day...though humidity levels
will likely remain elevated.

Thursday night into Friday the weak cool front will stall out just
to our south as a convectively-enhanced shortwave ripples eastward
along this boundary...with the medium range guidance packages
continuing to exhibit some differences on its strength...track...and
timing...factors that will heavily influence the extent to which any
associated pcpn will spread back across our region during this 24-
hour period. Given the resultant uncertainty...will continue to
cover the passage of this feature with a mix of slight chance to
chance PoPs...with the highest values located along the NY/PA
border.

After that the medium range guidance is in loose agreement on
another mid-level shortwave trough and surface low/weak cold front
crossing our region in the Friday night-Saturday period...albeit
with the usual differences in its timing...strength...and track
common at this distant vantage point. With this in mind have
continued to broadbrush lower-end chances for showers and storms for
the end of this period.

As for temperatures for the end of the week...these look to be on
the warm side with daily highs in the lower-mid 80s and nightly lows
in the 60s...while humidity levels should remain elevated with
surface dewpoints remaining in the 60s.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
Low VFR to MVFR cigs will be found across area terminals for much of
the day behind the cold front. A few showers will also be possible.

A secondary cold front will push through tonight. This will lead to
most areas experiencing MVFR cigs. That said...a few terminals
across the higher terrain might also see IFR cigs overnight.

Outlook...

Monday through Tuesday...VFR.
Wednesday...VFR/MVFR with showers and thunderstorms likely.
Thursday...Mainly VFR with a chance of a shower or thunderstorm
across the western Southern Tier.

&&

.MARINE...
A cold front will push across the Lower Great Lakes this morning. This
will lead to freshening winds that will veer to the west and has led to
a fresh round of small craft advisories for Lake Ontario.

The fresh to strong westerlies will persist into tonight before
approaching high pressure encourages winds and waves to subside late
tonight and Monday.

Nearly ideal conditons for recreational boating can then be expected
for Monday and Tuesday...as high pressure will cross the region.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...Beach Hazards Statement through this evening for NYZ002.
     Beach Hazards Statement through late tonight for NYZ003>006.
     Beach Hazards Statement until 8 PM EDT this evening for NYZ007.
MARINE...Small Craft Advisory from 2 PM this afternoon to 11 PM EDT
         this evening for LOZ042.
         Small Craft Advisory until 2 AM EDT Monday for LOZ043-044.
         Small Craft Advisory from 2 PM this afternoon to 8 PM EDT
         this evening for LOZ045.

&&

$$

SYNOPSIS...RSH
NEAR TERM...AR/RSH
SHORT TERM...JJR
LONG TERM...JJR
AVIATION...AR/RSH
MARINE...RSH