textproduct: New York

WHAT HAS CHANGED

No significant changes

KEY MESSAGES

1) A round of wet weather into this evening, then fog tonight into early Sunday morning.

2) Another round of rain from late Sunday afternoon into a portion of Monday.

3) Unsettled weather expected toward mid to late next week.

DISCUSSION

KEY MESSAGE 1... Low pressure passing to our north in Canada has lead to broad warm air advection showers developing across the area with a warm front. These showers are expected to increase in coverage west to east into the afternoon and evening. A mid-level shortwave along with a strong southerly 40-50 kt LLJ will provide most lift for these showers.

There is some elevated instability (around 500-800 J/kg of MUCAPE) seen in the latest 12Z CAMs, primarily across Long Island and NYC. Decent 0-6km bulk shear is also expected to develop in the same areas, 30-45 kt. Some of these showers are expected to become thunderstorms, primarily starting just east of NYC metro this afternoon, with better odds across Long Island into early this evening, before all precipitation exits east late this evening into early tonight.

Rainfall totals are around 0.4-0.6" across the area, with lower totals across areas far N & W of NYC. Localized totals near or just above an inch are possible in any heavier thunderstorms that may develop. Flood concerns are still minimal, at this time, and the rain is expected to be largely beneficial.

Confidence is higher for fog development tonight into early tomorrow morning after the rain ends, especially for Long Island and southern CT, where the fog could become locally dense late tonight. Should dense fog become widespread, a dense fog advisory may need to be issued.

KEY MESSAGE 2... Sunday morning and early afternoon looks to be mostly dry between systems as a cold front approaches from the west. Scattered showers are possible from mid to late afternoon from NYC north/west. A more organized rainfall event is then expected Sunday night into Monday as an amplifying upper trough sends the cold front across, with one or more weak frontal waves passing well to the south and east. Another 1/4 to 1/2 inch of beneficial rainfall is expected, with lesser amounts of 1/10 to 1/4 inch NW of NYC.

Highs on Sunday have the potential to near 80 degrees in portions of NE NJ and NYC metro. Otherwise, highs will be in the 70s across the area. The chance for thunder appears low in the afternoon/evening, but a few thunderstorms are possible given strong warming at the surface if timed well with lift from the frontal boundary.

KEY MESSAGE 3... Low pressure over the Northern Plains Tuesday is expected to dive southeast over the southern to central Great Lakes region Tuesday night, then eject off the Mid-Atlantic Coast late in the day Thursday into Thursday night. This coastal low then slowly heads northeast through the rest of the forecast period, with some slow strengthening.

An inverted trough extending northward from the low as it passes south of the area will likely be the primary focus for showers for late Wednesday into Wednesday night. Of course, this far out, there are timing differences with the track and strength of the low, which would lead to differences in timing of any precipitation and amounts. This also leads to high uncertainty with the track of the eventual coastal low that passes south and east of the area at the end of the week, and whether we see any rainfall as it heads out to sea.

OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY

Sunday Afternoon-Night: Mainly VFR. Chance of showers and MVFR in the evening. Showers likely, especially closer to the coast at night along with MVFR, potentially IFR at times.

Monday: Showers and MVFR early, especially near the coast, then VFR.

Tuesday: Mainly VFR. NW winds G15-20 kt possible in the afternoon.

Wednesday: Showers developing through the day. MVFR or lower conditions. S winds G15-25 kt in the afternoon and evening.

Thursday: Showers possible with MVFR or lower conditions.

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

MARINE

S winds 15-20 kt with gusts up to 25 kt on the ocean and the Long Island south shore bays this afternoon/evening, with ocean seas building to 5 or 6 ft, as well. Some 5-ft seas could linger into this evening on the ocean. We'll drop below SCA-levels on all waters tonight into Sunday morning. Sunday afternoon into Sunday night, another period of 5 ft seas is possible on eastern ocean waters with a cold frontal passage. Below SCA-criteria is then expected to remain through Tue Night.

Waves build late in the day Wednesday as a southerly flow increases due to an approaching low pressure system to the west. SCA conditions are possible for the ocean waters for a brief period from Wednesday afternoon into the first half of Wednesday night. Thereafter, winds and waves are expected to remain below SCA criteria.

OKX WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ345- 355. Small Craft Advisory until 11 PM EDT this evening for ANZ350- 353.