Henrietta, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

556
FXUS61 KBUF 181503
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
1103 AM EDT Sun May 18 2025

.SYNOPSIS...
Cool, breezy, and cloudy with scattered to numerous showers today.
Drier weather returns tonight as high pressure builds in for Monday
and Tuesday. Clear skies and lighter winds Monday night may result
in FROST in wind sheltered locations. Unsettled and cool weather
returns Wednesday and then last through the end of the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
A closed low over our region this Sunday morning will slowly
spiral eastward, with several waves of moisture rotating around
the low bringing batches of mainly light rain showers to our
region today. The greatest threat for rain will be from the
northern Finger Lakes and points eastward that will lie closer
to the upper level low...and also be within the vicinity of a
weak surface trough.

A saturated lower atmosphere could also bring patches of fog and
low ceiling heights as well as drizzle through the morning
hours, especially for the higher terrain east of Lake Ontario.

Drier weather will take hold tonight as high pressure builds in
across the region. Skies will begrudgingly clear with the
upslope northwest flow tonight, and overnight temperatures will
be cool with overnight lows in the low/mid 40s to upper 30s east
of Lake Ontario. Though chilly, clouds may hang around enough
over the Tug Hill to limit any frost potential.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
Cool, dry weather Monday through Tuesday as a wedge of high pressure
extends down across the Great Lakes from Hudson Bay. 850H temps
within a degree or two of 0C under mainly clear skies Monday night
could pose a risk for frost development, particularly across the
higher terrain areas east of the lakes. Main uncertainties stem from
a light gradient NNW flow in place, as well as residual cloud cover
across the far eastern zones overnight. CIPS analogs indicate a
potential for subfreezing sfc temps though with conflicting
probabilities and locations between the GFS/NAM, while NBM ensemble
probs for this are only around 15-25%.

Chances for rain increase Tuesday night as a closed low over the
upper Mississippi Valley begins to encroach on the southern Great
Lakes region. Most areas outside the Southern Tier should remain dry
until after daybreak Wednesday.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A closed low over the upper Mississippi Valley and an upper level
low near the south-central Ontario/Quebec border Wednesday morning
will gradually congeal to form a single deep, broad closed low
across the Northeast and Great Lakes regions that will linger
through at least Saturday. Concurrently, energy transferring east of
the Appalachians will result in renewed cyclogenesis off the Mid-
Atlantic coast by Thursday, with the resultant sfc low tracking past
the Gulf of Maine by Friday evening.

Still a fair amount of uncertainty in the details of how exactly
this dynamic pattern will evolve on a synoptic scale. At the least,
the large scale cool, moist cyclonic flow across the Great Lakes
lends high confidence in an unsettled stretch of weather with cloudy
skies, persistent chances for rain, and daytime highs running 10-15
degrees below normal. Enough elevated instability could be present
for a few tstorms Wednesday evening, though otherwise thunderstorm
chances are minimal.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
A cool moist cyclonic flow will bring scattered to numerous showers
to the area. Expect MVFR to IFR cigs and periodic lower vsby across
area terminals today, which will slowly improvement tonight to VFR.

Outlook...

Monday and Tuesday...VFR.

Wednesday and Thursday...IFR to MVFR with showers around.

&&

.MARINE...
A west to northwest flow on the Lakes today and into tonight
will maintain small craft conditions with winds into the lower
20 knot range increasing wave heights to just over 4 feet.

Surface high pressure will nose southward across the lower Great
Lakes later tonight and into the start of the new work week
with light winds and waves on the lakes.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 11 PM EDT this evening for LEZ040-
         041.
         Small Craft Advisory until 11 PM EDT this evening for
         LOZ042-045.
         Small Craft Advisory until 5 AM EDT Monday for LOZ043-044.

&&

$$

SYNOPSIS...AR
NEAR TERM...AR/TMA
SHORT TERM...PP
LONG TERM...PP
AVIATION...AR
MARINE...Thomas