Brookhaven, New York 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

550
FXUS61 KOKX 150001
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
801 PM EDT Wed May 14 2025

.SYNOPSIS...
Weak low pressure and a frontal boundary will advance toward the
region through Thursday. Another frontal system will move across
from Friday through Saturday. High pressure will gradually
return early next week as low pressure lingers just east of New
England. A frontal system may approach during the middle of
next week.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Upper level low that as been spinning off to the west over the
past several days has opened into a trough over the OH Valley
today, with a surface front and weak low draped across the Mid
Atlantic. Ridging in place has been shifting offshore, with the
local area in between, with prolonged easterly flow and
unsettled conditions.

Bands of light to occasionally moderate showers continue to
work through this evening. The bulk of these showers should
gradually weaken and exit to the north this evening. Areas of
fog likely develop, with potential to become dense overnight.
Temperatures largely remain steady tonight, falling back a few
degrees into the mid/upper 50s.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
Axis of the open trough tracks overhead on Thursday, with the
decaying surface low and warm front moving through locally.

Any morning fog should burn off by late morning, and
temperatures climb about 10 degrees above the previous day, with
afternoon highs in the lower 70s. Isolated to scattered pop up
convection is possible by late morning or early afternoon, with
the chance persisting into the early evening. A bit more mild
and moist surface conditions are expected, and 12Z HREF CAPE
values are progged up to 500-1000 J/kg. While the threat for
severe weather and significant hydrological concerns is low,
any thunderstorm could produce locally heavy rainfall.

Rain chances gradually lower by the evening, but a weak
pressure gradient and very light onshore flow Thursday night
likely allows fog to develop once again into early Friday
morning.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Key Points:

* An unsettled weather regime continues through Saturday.

* Showers and a few thunderstorms are expected Friday and
  Saturday mainly in the afternoon and evening, but it will not
  be a complete washout.

* An isolated shower possible inland Sunday afternoon, otherwise
  dry conditions should prevail through Tuesday.

* Temperatures will mainly run above normal through the weekend
  before trending closer to normal early next week.

A blocky synoptic pattern will continue through the middle of
next week. Models continue to depict a decaying line of
showers and possible thunderstorms approaching from the west on
Friday. They are in association with a weak area of mid level
shortwave energy out of ahead of the next upper low and trough
over the Northern Plains. The potential for showers and possible
thunderstorms appears highest in the afternoon and evening, and
mainly north and west of the NYC metro. Onshore flow further
east will likely limit instability and convection potential on
Friday.

The aforementioned upper low and trough will move over the Great
Lakes on Saturday helping to push the next frontal system into
the area. Conditions may become more conducive to showers and
thunderstorms and the latest NBM has increased PoPs from its
previous cycles. However, there are still factors that may limit
convective development including the main forcing remaining
well to our northwest and potential of some lingering mid level
dry air. The ECMWF appears the most aggressive with a well
defined complex of showers/storms moving across the area on
Saturday. The mesoscale setup will become better resolved over
the next few days, which should help give more confidence on the
evolution of potential convection on Saturday. Forecast precip
probabilities are again highest north and west of the NYC metro
and mainly in the afternoon and evening.

The frontal system and associated upper low/trough continue
sliding across the area Saturday night. Lingering showers
cannot be ruled out, but probabilities decrease through the
night. The system will then push east of the area on Sunday and
then remain near or just off the New England coast early next
week. Lingering cyclonic flow aloft Sunday may be enough to
produce a diurnally driven isolated shower well inland in the
afternoon. Upper ridging will build just to our west early next
week with another trough amplifying over the western states. The
proximity of the ridging and upper low just offshore should
keep conditions dry Monday into Tuesday. The NBM indicates an
increase in precip probabilities on Wednesday which may be
overdone given the nearby ridging which may take some time to
break down. Will indicate a low probability for now with
potential of another frontal system attempting to approach mid
next week.

&&

.AVIATION /00Z THURSDAY THROUGH MONDAY/...
Low pressure will remain to the south through the period.

Bands of showers will be exiting to the north this evening.
The bigger story will be low cigs and vsby especially after
midnight as E-ESE winds diminish and become light overnight,
and back to the NE or become variable. LIFR cond are likely and
should last until at least 14Z-15Z, and likely until around
16Z-17Z at KHPN/KGON.

Improvement to MVFR expected from KLGA north/west at some point
Thu afternoon. Confidence in IFR cond at the other terminals is
lower, and they could improve to MVFR late in the afternoon as
well.

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

Amendments likely for changing flight categories.

.OUTLOOK FOR 00Z THURSDAY THROUGH MONDAY...

Thursday night: Low clouds/fog with IFR/LIFR cond returning.

Friday: IFR/LIFR in the morning, then chance of MVFR in the
afternoon/evening with slight chance of tstms.

Saturday: MVFR cond expected, IFR possible, with showers likely
and chance of tstms.

Sunday...Mainly VFR.

Monday...VFR.

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

&&

.MARINE...
Small Craft Advisory extended for the NY Harbor until 9pm and remains
in effect for the ocean waters through Thursday evening. Winds
lighten on the harbor this evening, but ocean seas around 5 ft
likely linger into Thursday before lowering by Thursday night.

Conditions will remain below SCA levels Friday through next Monday
with a relatively weak pressure gradient over the waters.

&&

.HYDROLOGY...
Isolated heavy downpours could result in a quick inch of rainfall
and result in minor flooding of urban and poor drainage areas. This
threat appears limited and localized should it occur. QPF
through Thursday should average under a half inch. Additional
convection Thursday afternoon or evening could have the same result.
The overall threat for flash flooding remains low.

There are currently no hydrologic concerns Friday through early next
week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 9 PM EDT this evening for ANZ338.
     Small Craft Advisory until 6 PM EDT Thursday for ANZ350-353-
     355.

&&

$$

SYNOPSIS...DR/DS
NEAR TERM...DR/DS
SHORT TERM...DR
LONG TERM...DS
AVIATION...BG
MARINE...DR/DS
HYDROLOGY...DR/DS