970
FXUS61 KBUF 071004
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
604 AM EDT Sun Jul 7 2024

.SYNOPSIS...
High pressure will build across the region and bring fair and dry
weather through the start of the new work week. A slow moving cold
front will likely generate some rainfall in the form of showers and
thunderstorms Tuesday into Wednesday. Temperatures will be close to
normal today, and then above normal temperatures will return
ahead of the cold front Monday and Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
High pressure centered over the Ohio valley this morning will slowly
expand across the Lower Great Lakes through tonight. This will
result in fair and rain-free weather during the period. Patchy
fog in the Southern Tier river valleys will gradually dissipate
by mid-morning.

Some fair weather cumulus will develop along and inland of lake
breeze boundaries today, but subsidence associated with the
high pressure system will result in fair and pleasant weather
today. Highs will be in the upper 70s to lower 80s.

With high pressure overhead there will be good radiational cooling
conditions tonight. Hedge below model consensus for low temperatures
which should range from the mid 50s to lower 60s. This also will
result in fog development in the Southern Tier river valleys.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
Surface high pressure over our region to start this period will
drift eastward through the day. Some valley fog in the Southern Tier
and Black River Valley to start the day will quickly mix out with
dry air aloft. Behind this surface high, southerly flow will advect
a warmer airmass northward...with mid Celsius 850 hPa temperatures
mixing to the surface and supporting afternoon temperatures in the
mid 80s to around 90F. Dewpoints in the mid to upper 60s will leave
apparent temperatures only in the lower 90s.

Monday night and Tuesday our region will be near the advection of
tropical moisture from two separate source. A southerly flow will
bring Atlantic moisture northward from the Southeast. This moisture
will track into our Finger Lakes region. Meanwhile ahead of a mid
level trough, moisture from Tropical system Beryl will be streaming
by just to our west. Between these two moisture plumes, much of our
CWA will reside. This will leave Monday night mainly dry, while on
Tuesday some lake breeze circulation showers and thunderstorms may
form. Tuesday will also feature similar temperatures, but with
dewpoints now a few degrees warmer. This will bring heat index
values into the low to mid 90s for portions of the Genesee Valley and
Finger Lakes region.

Tuesday night as moisture from Beryl deepens across our region,
additional showers and perhaps thunderstorms will begin to increase
from the west.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
The 00Z models have begun to trend faster with the track of Beryl,
with signals for heavy rain potential for later Wednesday and
Wednesday night.

The two plumes of tropical moisture mentioned in the short term
will converge upon our region Wednesday, resulting in a deep
warm layer of over 14K feet with PWAT values 2.00 to 2.25
inches.

In the lower levels convergence ahead of a 35 knot LLJ, along with a
warm front draped over our region will combine with diffluent flow
aloft, and lift along multiple shortwaves to spread a period of rain
across our region. A mid level ridge may focus the better lift
(diffluent flow) aloft to our north and west Wednesday...resulting
in heavy rain to our west. But this heavier rain will advance into
our region. By Wednesday night the surface warm front will be
lifting towards the eastern Lake Ontario region, with a favored area
for heavy rain here overnight. At this time WPC has upgraded our
eastern two thirds of the CWA into a slight risk for excessive
rainfall through Wednesday night. There is still a lot of
uncertainty as to where the axis of heavier precipitation will be.

Wednesday and Wednesday night will also have chances for
thunderstorms, with MUCAPE values towards 1500 J/KG Wednesday
diminishing Wednesday night east of Lake Ontario.

The mid level trough will be slow to push eastward and flatten,
leaving chances for additional showers and thunderstorms Thursday
through Saturday, especially during the peak heating of the
afternoon. Heavy rain chances will be less this period with the axis
of deeper moisture now to the east, along with a weakening LLJ.

&&

.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
High pressure will provide fair weather for today and tonight.
Patchy fog may briefly impact KJHW through mid-morning, and
there is a small area of MVFR stratus northeast of Lake Erie
which will be near KBUF through mid-morning. After this, widespread
VFR flight conditions today, with sct-bkn afternoon cumulus
with bases 4-5k feet. These will dissipate this evening as the
high builds overhead. Southern Tier river valley fog is likely
again late tonight.

Outlook...

Monday...VFR.
Tuesday...Restrictions possible with showers and thunderstorms
likely.
Wednesday...Restrictions possible with a chance of showers and
thunderstorms.
Thursday...Mainly VFR with a low chance of showers and thunderstorms.

&&

.MARINE...
High pressure will build over the lower Great Lakes through early
next week. This will bring a period quiet conditions through mid
week with a weak pressure gradient favoring light winds and limited
waves. The light flow will allow for some local lake breezes to form
each day.

&&

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

&&

$$

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