NEAR TERM /UNTIL 6 AM FRIDAY MORNING/
A trough of low pressure stalls over us tonight with shortwave lift slowly shifting through. Ahead of this, sea breeze boundaries will act as other sources of low level moisture convergence. Scattered showers and thunderstorms will continue into tonight with SBCAPEs starting out at 500-1000 J/kg mainly west of the Hudson River heading into this evening, then still a few hundred J/kg MUCAPE overnight across most of the area. Strong gusts still possible with thunderstorms, but severe storms are unlikely as shear is lacking.

Minor/poor drainage flooding will be possible with thunderstorms as they move fairly slowly with a weak flow aloft. Still can't completely rule out flash flooding due to the slow motion of storm cells with plenty of moisture as PWATs average around 2 inches.

Warm and muggy conditions tonight otherwise, with potential for overnight stratus/fog development in a moist and weak flow environment.

SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/
Broad upper troughing across southeastern Canada retreats northward Friday into Saturday, with a low over the Great Lakes Friday shearing into Ontario/Quebec on Saturday. A weak shortwave moves east of the region Friday morning, with another weak shortwave approaching Friday afternoon.

It appears that the surface trough that will be across the forecast area will lift as a warm front during the day, aided by afternoon seabreeze development. Subsidence and mid-level drying in the wake of the departing shortwave should allow for a window for good heating after morning stratus/fog dissipates, leading to very warm and humid conditions (lower to mid 80s coast, to upper 80s to around 90 for NE NJ and LoHud). There's potential for isolated to scattered afternoon/eve convection in a marginally unstable and modestly sheared environment with the approach of the next shortwave, and in the vicinity of the warm front/seabreeze. This will be mainly for areas N&W of NYC. Lack of focus and a stabilizing marine layer to the east across the coast should limit shra/tsra activity thru early Friday evening. Strong storms possible with severe storm chances still limited by relatively weak 0-6km bulk shear, but perhaps a little stronger than today's shear. CAPEs will also probably be higher on Friday, so trends will need to be monitored for the severe threat.

An increasing threat for heavy downpours sliding west to east across the entire area for Friday night through Saturday morning. There will be strengthening mid/upper support ahead of shearing low to the west. There will also be a strengthening a low-level jet ahead of an advancing cold front and pre-frontal trough, advecting in an increasingly sub-tropical environment with weak instability, deep moisture with 2"+ PWATS, and a warm cloud layer.

The pre-frontal trough appears to stall over the area Saturday, with potential for scattered afternoon convection ahead/along it in the afternoon and evening. This appears to be the best chance of a few strong to severe thunderstorms, roughly over the NW half of the forecast area, based on moderate deep layer shear and SBCAPEs potentially around 2000 J/kg. The exact location of the trough will determine possible focus for training convection and a localized flash flood threat as the flow parallels the stalled boundary. More clarity on this part of the forecast in the next 24 to 36 hrs.
Activity should weaken in intensity as it translates to the coast with waning instability and a deepening coastal stable layer Saturday evening. The cold front will slowly move through the area during the night with the end of the shower/thunderstorm threat.

Finally, a hot and humid airmass brings the likelihood of heat advisory criteria being met for most of NE NJ for the Friday- Saturday period. A heat advisory has therefore been issued here for this period. Not enough confidence to include portions of the Lower Hudson Valley or Western Passaic County at this point, but it may be a close call. Surface dewpoints will have a tough time mixing out during peak heating with surface troughs in the vicinity both days a relatively moist boundary layer, and southerly-component surface winds. 850mb temps progged at 18-19C both days, perhaps slightly cooler Saturday vs Friday, and Saturday has more cloud potential.
Heat indices of 95-100 expected both days.

LONG TERM /SUNDAY THROUGH THURSDAY/
At the onset of the period, a weak cold front will pass just southeast of the area early Sunday morning with high pressure building in from the west into Monday. With the exception of some lingering showers for the south fork of Long Island and extreme southeast New London, Sunday should be dry, but will need to watch how far offshore the boundary gets. Shortwave energy embedded within the longwave trough to the west will then send a frontal system east across the Great Lakes and Ohio Valley states Monday night into Tuesday. his will bring increasing chance of convection Tuesday into Thursday.

A deep-layered SW flow during this time will maintain seasonably warm conditions across the area along with increasing humidity through Thursday. Daytime highs during this time will generally be in the mid and upper 80s away from the immediate coast, along with some lower 90s across metro NJ. Lows will mainly be in the upper 60s to lower 70s, warmest across the NYC metro. Max heat indices at this time look to fall just short of 95. Largely stayed close to national blended guidance for this update.

AVIATION /20Z THURSDAY THROUGH TUESDAY/
A weak cold front moves towards the region, stalling near the area tonight into Friday morning.

Outside of any scattered aft/eve showers and thunderstorms, generally looking at a VFR forecast through about 05z. The best chances for any convection will be across the Lower Hudson Valley.
Lesser confidence closer to NYC. There remains some uncertainty as to how quickly any activity weaken as it approaches the NYC terminals. East of NYC, confidence is rather low and will keep conditions dry for now, however can not rule out a few isolated showers.

MVFR/IFR conditions develop after 05z, primarily impacting the coastal terminals. The low cigs will continue into Friday morning, with slow improvement expected during the late morning into the early afternoon.

South winds around or slightly above 10 kt this afternoon. We could see some gusts up to 20 kt at the coast this afternoon. Winds lighten tonight, becoming light and variable overnight.

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

Amendments will be likely for the timing of showers and thunderstorms late this afternoon and evening.

KEWR may for a time become 140-150 due to a seabreeze in the afternoon.

OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY...

Friday and Saturday: MVFR or lower conditions possible at times with continued chance of showers/tstms.

Sunday and Monday: VFR.

Tuesday: Chance of showers and thunderstorms in the afternoon, mainly west of NYC.

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

MARINE
Sub-advisory conditions expected through the first half of Friday night. The exceptions are occasional gusts up to around 25kt late day/early evening near the entrance to NY Harbor eastward to western Great South Bay today and tomorrow. Winds and seas pick up on Friday night with SCA conds on the ocean mainly late at night. Being a late 3rd period start, will hold off on issuing a SCA for the ocean waters. SCA otherwise potentially needed on the ocean late Friday night through Saturday night.

Sub-SCA conditions expected Sunday into Tuesday with high pressure over the region.

HYDROLOGY
Scattered thunderstorms with heavy downpours producing 1-2"/hr rainfall rates are possible this afternoon/evening, mainly west of the Hudson River. The primary threat is for minor/poor drainage flooding.

Overall chances/coverage of showers and potential thunderstorm will be higher late day Friday through Saturday evening. Total rainfall amounts will vary greatly due to the convective nature, but an average of a half inch to inch of rainfall is anticipated during this period along with locally higher amounts. Once again, localized 1-2"/hr rainfall potential rates with scattered heavy downpours, but this time across the entire area. The primary threat will be minor urban/poor drainage flooding, but a localized flash flood threat will exist in path of any training convection.

At this time, no widespread hydrologic concerns expected for Sunday through Thursday. However, there is the threat for localized heavy rain with any thunderstorms that may develop Tuesday into Thursday.

TIDES/COASTAL FLOODING
There is a moderate to high risk for rip current development along NYC/LI ocean beaches today and Friday with a combo of building southerly wind wave and 2 to 3 ft E/SE swell. The high risk is for W LI and NYC beaches this aft/eve due to enhanced seabreeze formation and large tidal range, which is possible once again Fri aft/eve.

More widespread threat of high risk of rip currents for all NYC/LI ocean beaches possible on Saturday.

OKX WATCHES/WARNINGS/ADVISORIES
CT...None.
NY...High Risk for Rip Currents until 9 PM EDT this evening for NYZ075- 178-179.
NJ...Heat Advisory from noon Friday to 8 PM EDT Saturday for NJZ004- 006-103>108.
MARINE...None.