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FXUS61 KOKX 041954
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
354 PM EDT Tue Apr 4 2023

.SYNOPSIS...
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A backdoor cold front moves into the area tonight and remains in the vicinity through Wednesday. The front returns north as a warm front Wednesday night. A cold front approaches Thursday, moving through the region Thursday evening. High pressure will then build in from the Great Lakes through the weekend, sliding offshore by early next week.
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&& .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
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At 19Z a front extended from along the New York/Pennsylvania border eastward into the lower Hudson Valley and then across southern Massachusetts. With a colder airmass to the north, and with high pressure building southward through tonight this front will be pushed southward as a backdoor cold front. With the flow shifting to the north and northeast, the front will come through the the northern and eastern sections and then push farther to the south and west late tonight and likely be through the area by Wednesday morning. There will be little forcing with the boundary, and moisture will be shallow, with stratus developing. Right along the front there will be some better lift, and while much of the precipitation will be drizzle, along the front will have a slight chance of rain. Fog is not expected to develop until late tonight as the winds shift to the east and surface dew points begin to increase. There is some uncertainty with the overnight low temperatures, and will be dependent on how far west and south the front moves through the overnight hours.
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&& .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
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The front does become stationary somewhere in the vicinity. With a cool airmass and an easterly flow continuing as the high moves off the New England coast during the day, there will be weak cooler air damming as a more south to southeast flow remains to the west and south. With the front in the vicinity and shallow moisture in place will continue with the chance of drizzle and fog. As low pressure moves into southern Canada with a cold front approaching to the west late Wednesday night, the flow across the area will eventually shift to the south and the weak stalled boundary will either dissipate or move to the north as a warm front, however the best warm front formation will be well to the north late Wednesday night into Thursday morning. Will maintain a chance of drizzle, however, this may be overdone as the area may become warm sectored late at night with a dry period possible before showers move into the area with the cold front.
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&& .LONG TERM /THURSDAY THROUGH TUESDAY/...
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The period begins with the warmest day of the year so far for parts of the region. As an upper ridge axis slides offshore on Thursday, troughing over the Northern Plains begins to push east. This will lift a warm front north through the region early Thu morning, with increasing southwesterly flow. An attendant cold front approaches from the west late in the day, with the potential for convective development along and ahead of this boundary. After some lingering low clouds associated with the nearby warm front early in the day, expect a quick jump in temperatures as the BL mixes. Areas west of the Hudson River and away from the maritime influence of the cooler waters, expect temperatures to climb into the 70s, with isolated lower 80s possible in parts of urban NE NJ, or around 20 degrees above normal. It`s possible KEWR`s daily record high of 80 degrees could be challenged. Across Long Island and Southern Connecticut, the SW wind off the waters will hold temperatures down in the 60s, and even upper 50s along the immediate shoreline. Given the warm, moist air mass inland, there will be some amount of instability ahead of the front, with BUFKIT soundings indicating SBCAPE values of several hundred joules possible. SPC has a general thunder risk outlined for the entire area, with a marginal straddling parts of interior NE NJ and Orange County NY. Bulk shear 0-6 km values are progged between 40 and 60 kt, and ample moisture will be present as PWATs climb to over 1.5 in, or about as high as observed this time of year. Timing looks to be primarily in the afternoon and early evening, with the front itself following shortly thereafter into the evening. Fortunately, the flow looks pretty progressive, so not too concerned with hydrological issues from this system, though a quick quarter to half inch is possible. The primary threat from any strong to severe thunderstorm would be damaging wind gusts. Conditions dry out from west to east Thursday evening behind the front, with winds veering northwest, helping to advect in drier, cooler air to end the work week. Friday through the weekend will be dry as a 1035 mb surface high pressure builds in from the Great Lakes. Gusty NW winds 25 to 30 mph are possible on Friday as the high builds in, but then lower over the weekend. With the northwest flow, temperatures will be cooler during this time, generally 50s and lower 60s, with increasing sun through Sunday. The evolution of the large scale pattern becomes more uncertain to start next week. The latest model consensus has the surface high starting to move offshore, but lingering ridging may hold on during Monday. There may be an approaching upper trough, but the timing and amplitude continue to have little consistency. Generally stuck close to national blended guidance for this update.
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&& .AVIATION /20Z TUESDAY THROUGH SUNDAY/... A stationary front remains through the region today and then sags south of the terminals tonight as a cold front. Mainly VFR through 00z. Conditions will then lower tonight, becoming IFR and LIFR late tonight/early Wednesday morning. Drizzle or sprinkles are possible mainly late tonight/early Wednesday morning. SE to S winds around 10 kt or less. Winds become E-NE after around midnight as the cold front sags southward. Winds then increase 10-15 kt on Wednesday. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Chance that winds veer S at KEWR for a period late this afternoon into early evening. Wind shift to ENE may be off by 1-2 hours, otherwise moderate to high confidence in wind forecast. Moderate confidence in cigs tonight. Low to moderate confidence in vsbys. Drizzle might not occur tonight. ...OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY... Wednesday PM: MVFR/IFR with a chance of light rain or drizzle. E gusts 15-20 kt possible. Wednesday Night-Thursday Night: MVFR/IFR Wednesday night into Thursday morning. MVFR-VFR Thursday afternoon and night. Chance of showers with a slight chance of a thunderstorms Wednesday night, showers likely with a chance thunderstorms Thursday afternoon and evening. SW gusts 15-20kt, becoming W-NW Thursday night. LLWS possible late Wednesday night. Friday-Sunday: VFR. W-NW G20-25kt Friday morning. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90. && .MARINE...
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With a relatively weak pressure gradient in place through Wednesday evening winds and seas will remain below SCA levels across the forecast waters tonight into Wednesday evening. Southerly winds may be increasing late Wednesday night, especially across the western waters as a low pressure approaches to the west and a warm front lifts to the north. Will be toward morning before gusts and possibly ocean seas near SCA levels on the western waters. Being late in the 3rd period will hold off on issuing an advisory. Increasing SW flow on Thursday brings SCA conds to the ocean, with gusts around 25 kt and seas 4 to 6 ft into Thursday evening. Non- ocean waters are forecast to remain below SCA Thursday and Thursday night. SCA conditions are then possible on all waters Friday as high pressure builds in, potentially bringing NW gusts around 25 kt, before lowering Friday night. Sub-SCA conditions are expected on all waters through the weekend with high pressure in control.
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&& .HYDROLOGY...
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No hydrologic concerns are expected through early next week.
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&& .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...DR/MET NEAR TERM...MET SHORT TERM...MET LONG TERM...DR AVIATION...JC MARINE...DR/MET HYDROLOGY...DR/MET