Smithtown, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

797
FXUS61 KOKX 061819
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
219 PM EDT Sun Jul 6 2025

.SYNOPSIS...
High pressure remains offshore into Monday. Weak low pressure
passes nearby Monday afternoon into Monday night. A cold front
approaches Tuesday and moves over the area Tuesday night. The
front likely stalls nearby the rest of the week leading to
unsettled conditions, potentially into next weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Warm and increasingly muggy conditions are expected tonight as
high pressure remains offshore. SW flow will advect
increasingly higher dew points through the night and help
increase lower level moisture. Some fog is possible overnight,
especially the eastern half of the area and close to the coast.
There should otherwise be increasing clouds through day break
Monday. Conditions will remain dry as there is no forcing for
any showers through day break. Lows will be in the upper 60s
inland to lower and middle 70s near the coast.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
Key Messages...

*Showers and possible thunderstorms late Monday morning into Monday
evening, especially in the vicinity of the NYC metro, NE NJ into
Lower Hudson Valley, could produce locally torrential downpours.
Localized flash flooding is possible from any of these
showers/storms.

*Warm and humid conditions Monday and Tuesday with max heat indices
in the lower 90s Monday and mid to upper 90s on Tuesday.

*Showers and thunderstorms possible Tuesday afternoon and evening
with a continued chance of locally heavy downpours.

The main concern on Monday will be the development of showers and
possible thunderstorms late morning into the afternoon. The
extratropical remnant circulation of Chantal will likely track over
the Delmarva in the afternoon and then offshore Monday evening and
night. It should be emphasized that the circulation will no longer
be tropical, but leftover tropical moisture will be present
across the northeast. This moisture will act on the sea breeze
boundary as well as some middle level energy to promote the
development of showers and a few thunderstorms. PWATs are quite
high and range from 2-2.25 inches. There is some question to the
amount of instability, but model soundings indicate a long and
relatively skinny CAPE, which is common in more tropical air
masses. Freezing levels look to average around 15kft as well,
supportive of efficient/warm rain processes. The 12z CAMs all
signal convective development across portions of NE NJ into the
Lower Hudson Valley, potentially into the NYC metro. Elsewhere,
showers are possible but coverage looks to be lower and could
just be isolated. No flood watch has been issued at this time,
but WPC has placed NE NJ, NYC metro, and Lower Hudson Valley in
a marginal risk for excessive rainfall.

Basin averaged rainfall amounts around one quarter of an inch
possible with some local areas receiving 1-2 inches with higher
amounts. Some locations may see little to no rainfall through Monday
evening.

Focus for showers shifts to the eastern part of the area Monday
night with the weak wave of low pressure passing to our south.
It appears most of the coverage should be offshore, but cannot rule
out some showers or isolated thunderstorms across portions of Long
Island or even southeast Connecticut.

For Tuesday, a cold front slowly approaches from the north and west.
Ahead of the front, tropical moisture will linger with PWATs around
2 inches. Showers and thunderstorms are likely to develop in the
afternoon and evening along and ahead of the cold front from the NYC
metro on NW. This activity will then slide eastward in the evening
and at night. The main concern from this activity will once again be
torrential downpours and localized flash flooding. WPC continues to
place the entire area in a marginal risk for excessive rainfall on
Tuesday. An isolated severe thunderstorm is possible Tuesday
afternoon/evening and SPC has much of the area in a marginal
risk.

No heat advisories have been issued at this time for Monday and
Tuesday. Temperatures have continued to trend slightly lower for
Monday, likely due to increasing cloud cover and earlier timing of
convection. Highs looks to range from the middle to upper 80s with
max heat indices in the lower 90s. It will be warmer on Tuesday as
highs should be in the upper 80s to lower 90s. There is still some
question to the amount of cloud cover and how high dew points will
be in the warmest part of the day. There are hints at the flow
becoming more SW-W which could lower dew points a bit. Heat indices
should be higher, in the middle to upper 90s. Have held off on the
issuance of a heat advisory for Tuesday since this is just one day
occurrence and there is little to no coverage of heat indices
above 100.

The front moves over or just east of the area Tuesday night. The
front may begin stalling nearby, which could promote continued
showers/storms for the eastern half of the area.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
The NBM was generally followed given the unsettled nature of
the pattern for the extended period.

A stalled front south of the area on Wednesday will remain in
the general vicinity through the end of the week and into the
weekend. High pressure over the western Atlantic will allow for
the persistent advection of moisture over the front and into the
area through much of the week. This will lead to the
development of scattered showers and storms through much of the
middle and end of the week, though storms are generally more
likely in the afternoon and early evening hours with the
presence of daytime heating.

Additional energy in the flow approaches the area by the end of
the week and may result in another round of showers and storms,
though guidance has been backing off on high pressure building
in thereafter. Unsettled conditions may persist through the
weekend.

Despite the ample cloud cover and general unsettled conditions this
week, temperatures should be right around average for this time of
the year with highs each day in the low to middle 80s.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
High pressure this afternoon weakens tonight and Monday as a weak
wave of low pressure approaches from the south.

VFR through this evening with mostly MVFR/IFR developing
overnight. Improvement back to mostly VFR on Monday, however showers
with a chance of thunderstorms starting at around noontime bring
lower flight categories.

S-SW winds 10-15kt with gusts around 20kt bcmg more southerly
tonight and diminishing. Winds pick up from the south on Monday,
increasing back to 10-15kt with possible gusts around 20kt.

 ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

Gusts today may be only occasional.

.OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY...

Monday through Friday: Primarily VFR each day with mainly afternoon
and evening showers/tstms possible with MVFR or IFR cond. Highest
chance exists from late Mon through Tue evening.

Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90

&&

.MARINE...
A few gusts close to 25 kt are possible on the ocean this
afternoon/evening. Otherwise, conditions will remain below
SCA levels on the waters through Monday. Seas begin building
Monday night into Tuesday and may approach 5 ft east of Moriches
Inlet into Tuesday night from a SE swell. Generally weak flow
will result in sub-SCA conditions on all waters through at least
Friday.

&&

.HYDROLOGY...
Locally torrential downpours are possible late Monday morning into
Monday evening, especially across NE NJ, NYC metro, and Lower Hudson
Valley. This activity could produce localized flash flooding and WPC
has this area in a Marginal risk for excessive rainfall. The risk
for locally torrential downpours and localized flash flooding
remains possible on Tuesday for the entire area. WPC has maintained
a marginal risk for excessive rainfall for Tuesday.

&&

.TIDES/COASTAL FLOODING...
The rip risk for all beaches will be moderate both today and
Monday, given the southerly flow and increasing southerly swell.
Surf heights around three ft are likely over the period, but
may increase to near 4ft by Monday, especially across NYC,
Nassau and western Suffolk beaches.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Air Quality Alert until 11 PM EDT this evening for CTZ005-009.
     Air Quality Alert from 11 AM to 11 PM EDT Monday for CTZ005-
     009.
NY...Air Quality Alert until 11 PM EDT this evening for NYZ069>075-
     176-178.
NJ...Air Quality Alert until 11 PM EDT this evening for NJZ002-004-
     006-103>108.
MARINE...None.

&&

$$

SYNOPSIS...DS/MW
NEAR TERM...DS
SHORT TERM...DS
LONG TERM...MW
AVIATION...JC
MARINE...DS/MW
HYDROLOGY...DS/MW
TIDES/COASTAL FLOODING...