094
FXUS61 KOKX 142002
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
402 PM EDT Wed May 14 2025

.SYNOPSIS...
-- Changed Discussion --
Weak area of low pressure and frontal boundary advances toward the region through Thursday. Another frontal system moves across the area Friday through Saturday. High pressure gradually returns Sunday into early next week as low pressure lingers just east of the New England coast. A frontal system may approach the middle of next week.
-- End Changed Discussion --
&& .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
-- Changed Discussion --
Upper level low that as been spinning off to the west over the past several days has opened into a trough over the OH Valley today, with a surface front and weak area of low pressure draped to our south across the Mid Atlantic. Ridging in place has been shifting offshore, and sandwiched in between the two is the local region, resulting in prolonged easterly flow, with unsettled conditions. Stream of showers continues working north and east through the region this afternoon, and will persist into at least early evening as a LLJ works through. A few elevated thunderstorms earlier have dissipated, but can`t rule out a few more isolated rumbles of thunders into early evening. More likely, periods of showers, with a few locally heavy downpours embedded in the activity. While additional QPF should be relatively light, at or under half an inch, the heavy downpours could result in localized minor flooding, especially in the typical poor drainage locales around the urban metro. The bulk of the showers gradually weaken and exits the region this evening as the best lift works north. Areas of fog likely develop, at least patchy, with potential to become dense. Will need to monitor overnight should a headline be needed. Temperatures largely remain steady tonight, falling back a few degrees into the mid to upper 50s.
-- End Changed Discussion --
&& .SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
-- Changed Discussion --
Axis of the open trough tracks overhead on Thursday, with the decaying surface low and warm front moving through locally. Any morning fog should burn off by late morning, and temperatures climb about 10 degrees above the previous day, with afternoon highs in the lower 70s. Isolated to scattered pop up convection is possible by late morning or early afternoon, with the chance persisting into the early evening. A bit more mild and moist surface conditions are expected, and 12Z HREF CAPE values are progged up to 500-1000 J/kg. While the threat for severe weather and significant hydrological concerns is low, any thunderstorm could produce locally heavy rainfall. Rain chances gradually lower by the evening, but a weak pressure gradient and very light onshore flow Thursday night likely allows fog to develop once again into early Friday morning.
-- End Changed Discussion --
&& .LONG TERM /FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
Key Points: *An unsettled weather regime continues through Saturday. *Showers and a few thunderstorms are expected Friday and Saturday mainly in the afternoon and evening, but it will not be a complete washout. *An isolated shower possible inland on Sunday afternoon with otherwise dry conditions prevailing through Tuesday. *Temperatures will mainly run above normal through the weekend before trending closer to normal early next week. A blocky synoptic pattern will continue through the middle of next week. Models continue to depict a decaying line of showers and possible thunderstorms approaching from the west on Friday. They are in association with a weak area of mid level shortwave energy out of ahead of the next upper low and trough over the Northern Plains. The potential for showers and possible thunderstorms appears highest in the afternoon and evening, and mainly north and west of the NYC metro. Onshore flow further east will likely limit instability and convection potential on Friday. The aforementioned upper low and trough will move over the Great Lakes on Saturday helping to push the next frontal system into the area. Conditions may become more conducive to showers and thunderstorms and the latest NBM has increased PoPs from its previous cycles. However, there are still factors that may limit convective development including the main forcing remaining well to our northwest and potential of some lingering mid level dry air. The ECMWF appears the most aggressive with a well defined complex of showers/storms moving across the area on Saturday. The mesoscale setup will become better resolved over the next few days, which should help give more confidence on the evolution of potential convection on Saturday. Forecast precip probabilities are again highest north and west of the NYC metro and mainly in the afternoon and evening. The frontal system and associated upper low/trough continue sliding across the area Saturday night. Lingering showers cannot be ruled out, but probabilities decrease through the night. The system will then push east of the area on Sunday and then remain near or just off the New England coast early next week. Lingering cyclonic flow aloft Sunday may be enough to produce a diurnally driven isolated shower well inland in the afternoon. Upper ridging will build just to our west early next week with another trough amplifying over the western states. The proximity of the ridging and upper low just offshore should keep conditions dry Monday into Tuesday. The NBM indicates an increase in precip probabilities on Wednesday which may be overdone given the nearby ridging which may take some time to break down. Will indicate a low probability for now with potential of another frontal system attempting to approach mid next week.
-- End Changed Discussion --
&& .AVIATION /20Z WEDNESDAY THROUGH MONDAY/... Low pressure remains south of the terminals through the TAF period. Rain along with MVFR to IFR conditions can be expected at all the area terminals. There may be intermittent improvement to VFR for a brief period or two. Winds will be from the E-ESE around 15kt with some gusts to 20-25kt. Any gusts diminish this evening. Winds diminish further, with some locations becoming light and variable. As they do, expect LIFR conditions to develop again tonight. There is the slight chance of a tstm mainly during the afternoon hours today. Coverage still too vague to mention in TAF. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Amendments likely for changing flight categories. .OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY... Thursday: Slight improvement during the afternoon, possibly becoming MVFR in the afternoon with chance of showers and possibly a tstm. Thursday night: Low stratus/fog with IFR/LIFR cond. Friday: IFR/LIFR in the morning, then chance of MVFR in the afternoon/evening with slight chance of tstms. Saturday: Chance of MVFR and showers. Slight chance of tstms. Sunday...Mainly VFR. Monday...VFR. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE...
-- Changed Discussion --
Small Craft Advisory remains in effect for the ocean waters and has NY Harbor with gusts near 25 kt, and seas at or above 5 ft on the ocean. Winds lighten on the harbor this evening, but ocean seas likely linger into Thursday before lowering by Thursday night. Conditions will remain below SCA levels Friday through next Monday with a relatively weak pressure gradient over the waters.
-- End Changed Discussion --
&& .HYDROLOGY...
-- Changed Discussion --
Isolated heavy downpours could result in a quick inch of rainfall and result in minor flooding of urban and poor drainage areas. This threat appears limited and localized should it occur. QPF through Thursday should average under a half inch. Additional convection Thursday afternoon or evening could have the same result. The overall threat for flash flooding remains low. There are currently no hydrologic concerns Friday through early next week.
-- End Changed Discussion --
&& .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ338. Small Craft Advisory until 6 PM EDT Thursday for ANZ350-353- 355. && $$ SYNOPSIS...DR/DS NEAR TERM...DR SHORT TERM...DR LONG TERM...DS AVIATION...BC MARINE...DR/DS HYDROLOGY...DR/DS