000
FXUS61 KOKX 131813
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
213 PM EDT Sat Apr 13 2024

.SYNOPSIS...
A large area of low pressure encompassing eastern Canada and the
Northeast will lift north and east through tonight. High pressure
will then build across the area late tonight into Sunday morning.
A weak wave of low pressure will drag a warm front followed by a
cold front across the area Sunday night into Monday morning. High
pressure returns for Monday and Tuesday. A slow moving warm front
then approaches the area from the southwest Wednesday followed by
a cold front late in the week as low pressure passes well to the
northwest.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --
Minor adjustments with temperatures with the max temperatures. These are expected to be mainly in the range of upper 40s for interior sections to lower 50s for much of the rest of the area, with some mid 50s for Eastern Long Island. Do not expect much further rise in temperatures for the rest of the afternoon. With a less than saturated environment, not all areas will have rainfall reach the ground. There are expected to be isolated to widely scattered rain showers through the day. The rain is expected to be mainly light and just end up being rain sprinkles for some areas. CAMs are in pretty good agreement in the shower activity with their reflectivity forecasts. The cold pool aloft with the deep trough is depicted very well in the upper level water vapor satellite imagery. The trough will be slowly moving across during today. This will keep cyclonic flow, abundant clouds and the isolated to scattered shower coverage. Appears that the gusty westerly flow is allowing for downslope so relatively more vertical mixing and relatively warmer temperatures are forecast along the coast compared to farther inland. CAMs shows best chance of showers across the Litchfield Hills of Western CT and eastern portions of the Lower Hudson Valley due to a westerly upslope flow. Elsewhere, expect sparse coverage. It will also be gusty with west winds gusting 30 to 40 mph, highest around NYC and Western Long Island based on what has been observed so far. For tonight, winds will gradually subside as low pressure lifts away and weak high pressure begins to build in from the west. Skies will clear and lows will return to normal.
-- End Changed Discussion --
&& .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/... Weak ridging both aloft and at the surface will quickly move to the east on Sunday as jet energy races across the Upper Great Lakes and into the Northeast late in the day. At the surface, weak low pressure passes to the NW will send a warm front through the area Sunday evening, closely followed by a cold frontal passage. Warm advection during the day may produce a few showers inland, but the best chance will come in the evening into the first half of the night as the frontal system interacts with modest lift and marginal instability. While unidirectional wind profiles feature 40-50kt of deep layer shear, the front is coming through after peak heating, and any organized convection approaching from the northwest will likely undergo weakening. At this time, have a chance of showers with a slight chance of thunderstorms. SPC does have areas north and west of the NYC metro under a marginal risk of severe weather. The main threat would be localized damaging winds. Confidence is low at this time. West winds ahead of the system on Sunday will back to the SW-S and gusts 20 to 30 mph in the afternoon. It will be mild with highs generally in the 60s just inland of the coast, to around 70 for the NJ metro. The cold front then works across the area from NW to SE, during the evening into early morning hours Sunday night. Expect a mild night with lows 7 to 10 degrees warmer than the previous night. High pressure returns for Monday with continued mild conditions. West winds should allow immediate coastal locations to even get a bit warmer. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... *Key Messages* *Unsettled conditions from mid to late week with daily shower chances. *A period of warmth with above normal temperatures expected Tuesday through Thursday. Not much change in the forecast thinking for this period and have stuck close to the NBM with some adjustment for PoPs mid to late week. Ensemble means in decent agreement with synoptic scale ridging to start the period followed by a deamplification to a more zonal flow by the end of the workweek. As for the sensible weather, mainly dry conditions expected through Wednesday AM, when a warm front attached to a deepening sfc low across the country`s midsection approaches from the southwest by afternoon. Shower chances increase through the day Wed as the front slowly moves north, or stalls over the area. While PWATS look to be over an inch, better forcing is found back to the west, so expecting mainly light rain at this point. Area is then warm sectored Thursday afternoon as a cold front approaches from the west. Global ensemble mean soundings (per DESI) show a few hundred J/kg of SBCAPE with some marginal shear, so potential is there for a few thunderstorms, and have reflected this with slight chance thunder across north and western sections of the area Thu afternoon as the cold front passes through. Friday remains unsettled as another quick moving frontal system impacts the area, with shower chances remaining. Temperatures will remain above normal for much of the week. Tuesday looks to be the warmest day under weak westerly flow, with only a few degrees of spread in the NBM adding to forecast confidence in low 70s for NYC and NE NJ with upper 60s elsewhere. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --
High pressure builds toward the terminals today. Low pressure approaches from the Great Lakes on Sunday. VFR through the TAF period. WSW to W winds of 15 to around 20 kt with gusts around 25-35 kt. Winds may shift toward 290-300 true as a surface trough moves through the terminals through 21Z. Winds begin to taper after 00Z Sunday, with gusts completely gone between 06-09Z. Winds shift to the S to SW Sunday morning, with gusts returning by the late morning to early afternoon at 25 to 30 kt. Low end VFR in stratocumulus cloud cover/ceilings continue for the remainder of this afternoon with clouds diminishing this evening. Spotty showers possible this afternoon as well, but with little, if any impact to flight categories. Some high end MVFR possible at KSWF in -SHRA this afternoon, but confidence low. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Ending time of gusts early Sunday may be +/- a few hours. Winds may shift more toward 290-300 true with the passage of a surface trough. OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY... Sat night: VFR W-NW winds gust around 25kt. Sunday: Mainly VFR. Chance of MVFR and showers in the afternoon. SW-W winds G20-25kt. Mon through Tue: Mainly VFR. Wed and Thu: Slight chc of MVFR late Wed. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90
-- End Changed Discussion --
&& .MARINE...
-- Changed Discussion --
Keeping headlines on the waters the same as previous forecast with wind gusts well into gale force near the coast in the vicinity of NYC, NY Harbor and Western Long Island ocean shorelines. Marine forecast mainly on track. Gales remain in effect for the ocean waters and NY Harbor through the day, with the remaining waters under a SCA through the first half of tonight. A large area of low pressure across eastern Canada and the Northeast will slowly track away from the area through tonight, Winds will gradually diminish late in the day through the night as weak high pressure builds in from the west. There could be a brief respite Sunday morning on the ocean before SCA conditions return in the afternoon. Gusts will subside late Sunday night, but SCA seas may linger in Monday afternoon. Sub small craft conditions are likely on all waters through midweek.
-- End Changed Discussion --
&& .HYDROLOGY... No hydrologic concerns exist throughout the forecast period. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory until 2 AM EDT Sunday for ANZ331-332-335- 340-345. Gale Warning until 6 PM EDT this evening for ANZ338-350-353- 355. && $$ SYNOPSIS...DBR/DW NEAR TERM...JM/DW SHORT TERM...DW LONG TERM...JP/DBR AVIATION...JP MARINE...JM/DBR/DW HYDROLOGY...DBR/DW