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FXUS61 KOKX 311457
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1057 AM EDT Sun Mar 31 2024

.SYNOPSIS...
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Weak high pressure settles in today. Another low pressure approaches from the west tonight, passing to the south on Monday. A stalled front south of the area Monday night into midweek will have lows developing along it. The relatively strongest low develops along it in the Mid-Atlantic toward midweek. This low traverses south of Long Island Wednesday night and eventually off the New England coast Thursday night. High pressure stays west of the area with low continuing to track slowly east Friday into Saturday.
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&& .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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A weak 1016 mb high over Michigan quickly slides east over the region today. This will keep dry conditions in place through this evening, with varying degrees of cloud cover streaming east in W/NW flow. The final day of the month will feature temperatures running about 5 degrees above normal, with most areas topping out in the mid to upper 50s, and the lower 60s in the urban metro.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
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Another wave of low pressure swings by tonight into Monday. Clouds become overcast Sunday evening. A band of strong 850mb warm air advection and forcing approaches the area Monday morning and afternoon. It has a northwest to southeast orientation to it and will likely lead to higher rain totals with periods of moderate to heavy rain. In addition, the area is located under the left exit region of an upper-level jet streak. Totals will range between 0.10" to 0.5" with the higher totals concentrated in NE NJ, NYC metro and LI. PWATs will reach around 0.9" during the peak period of forcing which is around the 90th percentile for this time of year per SPC`s Sounding Climatology page. Should the band of stronger forcing shift north or south, the area of heavier rainfall and higher totals will shift with it. This too will be a fast system, with much of the rain ending by early afternoon. As a result, flood benchmarks will not be reached. Temperatures will remain above normal tonight due to the cloud cover, but with the easterly flow and rain Monday, temperatures will budge little. Highs Monday will be around 50, which is several degrees below normal.
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&& .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
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Long wave ridge in the mid levels will be starting place for the local region Monday night into Tuesday. The upper level jet pattern will be zonal. The 250mb jet streak SW to NE Pacific into Mexico extends northeast to South Central US and then branches into Great Lakes as well as Carolinas. The upper level jet pattern becomes more active towards the middle of the week coinciding with a diving strong mid level shortwave from South Central Canada. Left front quad of the jet gets closest to the area for late Tuesday night into early Wednesday. This cutoff low approaches the area Wednesday and eventually moves into the Northeast Thursday into Friday, gradually making its way east to the NW Atlantic going into next weekend. At the surface, there will be a stalled front south of Long Island with multiple lows developing and traveling along it Monday night into the middle of the week. The low Tuesday night into Wednesday looks to be the stronger one according to the consensus of forecast model guidance. This low eventually moves northeast of the area going into latter half of this week. Rain is in the forecast Monday night through Thursday. Conditions then trend drier Thursday night with dry conditions expected Friday into Saturday. Potentially the rain could be heavy at times especially for midweek. Elevated instability will present a slight chance of thunderstorms as well around the middle of this week, particularly near the coast. Wintry precipitation remains possible as well for the interior while for the coast this precipitation will be mainly plain rain. Temperatures average below normal overall during the long term. Forecast highs stay in the 40s Tuesday, Wednesday and Thursday. Forecast highs trend higher Friday into next weekend and get relatively closer to normal values. Winds will become quite gusty Tuesday night through Thursday night but at this time, forecast values are below wind advisory thresholds. More detailed analysis focused on the low pressure storm system for mid to late week as well as surface winds is discussed below. The main feature at the surface will be the origin of cyclogenesis Tuesday night and its subsequent evolution through mid to late week. The models have a general consensus of depicting this low to move northeast from the Mid-Atlantic towards New England going from mid to late week and then slowly moving the low farther offshore. Models have exhibited large differences from each other as well as from the same model but from an earlier run. The low position and movement has widely varying depictions amongst large scale numerical weather prediction models of the GFS, ECMWF, and Canadian models for Thursday. An example of a significant change is within the ECMWF model which has trended relatively weaker with this storm system for the middle of the week. The rainfall within a 24 hour period according to the grand ensemble still has differences between extremes amounting to near 2.5 inches which is a half inch less than where the differences were looking at the same grand ensemble the previous night. The same grand ensemble also continues to convey the possibility of measurable snow especially for interior areas. Regarding winds, there is forecast to be an extended period of easterly winds, building fetch and seas. There will be some minor coastal flooding heading into midweek. See tides/coastal flooding section for more details. Winds are forecast to become more northeast to north Wednesday night and then northwest Thursday into the start of next weekend. Highest forecast gusts are forecast in the Tuesday night through Thursday night time period, with gusts along the coast getting near 35 to 40 mph.
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&& .AVIATION /14Z SUNDAY THROUGH THURSDAY/...
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High pressure centered over the Great Lakes this morning will build east and into the area by this evening. A fast moving wave of low pressure approaches from the west late tonight and passes to the south on Monday. VFR through much of tonight. MVFR to IFR develops in rain Monday morning. Increasing NW flow becomes WNW by this afternoon at 10-15 kt. Occasional gusts up to 20 kt are possible late morning into the afternoon. Chance of a brief seabreeze at KBDR this afternoon. Winds weaken again, likely becoming variable tonight into Monday morning. E-SE winds at 5-10 kt develop Monday morning. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Occasional gusts up to 20 kt possible today. OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY... Monday: MVFR-IFR in rain, especially in the morning and early afternoon. Tuesday: IFR in rain. E-ENE gusts 20-25 kt. Wednesday: IFR in rain. E-NE gusts 25-35 kt possible. The rain could be mixed with wet snow well inland late. Thursday: MVFR or lower with showers possible, possibly mixed with snow inland. NW gusts 25-35 kt. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90
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&& .MARINE... Winds and waves will remain below SCA criteria through Monday. Winds and waves will trend higher Monday night but are forecast to stay below SCA criteria. SCA conditions become more likely Tuesday and especially going through the midweek period. There will be potential for gales Tuesday night through Thursday night. && .HYDROLOGY... A brief period of moderate to heavy rainfall is possible Monday morning with totals of 0.25"-0.5" for NE NJ, NYC metro and LI. The rain quickly exits Monday afternoon, so flood benchmarks will not be reached. An extended forecast period of rainfall is forecast Monday night through Thursday. It will not rain the entire timeframe but the bulk of the rainfall can be expected Tuesday through Wednesday night. Heavy rainfall will be possible at times but exact rainfall amounts cannot be determined at this time due to low confidence. Poor drainage and low lying areas could very well experience some minor flooding with an overall marginal flood threat. && .TIDES/COASTAL FLOODING... Astronomically, by the middle of this week, we will be past the halfway point between the full and the new moon cycles. There will thus be an increase in the tidal levels around high tide. This combined with a long period and increasing easterly flow early to mid week will lead to more fetch and piling of water. For some shorelines particularly across the lower NY Harbor, South Shore Bays and Western Long Island for late Tuesday night into Wednesday around the times of high tide, minor coastal flooding will be possible. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JM/BR/DR NEAR TERM...JM/BR/DR SHORT TERM...BR LONG TERM...JM AVIATION...BR MARINE...JM/BR HYDROLOGY...JM/BR TIDES/COASTAL FLOODING...