NWS Forecaster Discussion
OKX
Area Forecast Discussion National Weather Service New York NY.
000 FXUS61 KOKX 101150 AFDOKX Area Forecast Discussion National Weather Service New York NY 750 AM EDT Sat Jun 10 2023 .SYNOPSIS... High pressure builds into the area today and exits offshore Sunday. Low pressure moves into the area from the west on Monday and pushes a cold front through the area Monday night. Surface low moves farther northeast of the area Tuesday into Tuesday night. Another low approaches Wednesday into Wednesday night but stays north of the area. Yet another low and associated cold front approach and move in late Thursday into Friday. && .NEAR TERM /THROUGH TONIGHT/... Forecast on track with only minor adjustments to reflect the most recent observations. The trough that was positioned over the area over the last week finally lifts to the northeast giving way to rising heights and weak ridging in the mid-levels. This will result in a mainly dry and mostly sunny day with temperatures rising into the middle to upper 70s. Though the trough departs today, some weak instability may develop for northern portions of the area allowing for a chance of an isolated shower into the afternoon. Any shower dissipates tonight as weak surface high pressure builds into the area from the south. A weak south flow develops allowing for some subtle moisture advection into the area. Lows tonight will be generally in the middle to upper 50s. the NYC metro may not drop out of the low to middle 60s. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... As mid-level ridging maximizes in the area on Sunday and a light south to southwest flow develops, high temperatures are expected to rise to at or above average for mid-June with much of the areas highs in the low to middle 80s. Some spots in and around the NYC metro may approach 90. General onshore flow will allow for an increase in cloud cover ahead of the next developing low pressure system to the west. A surface low pressure system developing to the west on Sunday will push a warm front moves through the area Sunday night and into Monday. This will allow chances of showers to increase through Sunday night into Monday morning. The cold front approaches the area on Monday with highs in the middle to upper 70s. This warmth may allow for some weak instability to develop toward the afternoon ahead of the cold front. This will enhance the potential for more widespread moderate rainfall, especially for the westernmost areas Monday afternoon into early evening. The front progresses eastward Monday night and into early Tuesday. Right now, WPC has the western portions of the area in a marginal risk for excessive rainfall for Monday afternoon and into the evening. Rainfall totals of an inch are expected for parts of the Lower Hudson Valley and into portions of NE NJ. && .LONG TERM /TUESDAY THROUGH FRIDAY/... In the mid levels, a large cutoff low approaches the region from the west Tuesday through Tuesday night. At the surface, a secondary low, as part of a well occluded parent low back in the Great Lakes, is forecast to be moving farther northeast of the region Tuesday through Tuesday night. The main parent low will also be moving northeast as well. Chances for rain showers will remain in the forecast for the region. For Wednesday, the mid level cutoff low continues to approach from the west but its center will stay north of the region. Here is where the different numerical weather prediction exhibit differences with respect to the speed of this feature. GFS keeps it more intact while the ECMWF and Canadian models show the low becoming more progressive and moving faster. The model differences carry into Wednesday night with ECMWF and Canadian showing the low in the Canadian Maritimes by early Thursday morning while the GFS keeps a slower speed to the low and having it still in New England early Thursday. At the surface, there is model agreement that the low approaching from the west Wednesday into Wednesday night will not have much moisture with it and will remain north of the area. Rain showers will become more likely Wednesday along with a slight chance of thunderstorms for the afternoon into early evening. Models indicate some increase in low level instability for parts of the region Wednesday afternoon. Rain shower chances decrease Wednesday night as highest positive vorticity advection shifts farther east of the region with the movement of the mid level low farther northeast of the region. Brief high pressure at the surface will build in from the south with slight height rises in the mid levels. After brief weak high pressure and dry conditions late Wednesday night into early Thursday, another low and associated front approach and move for the late Thursday into Friday timeframe. This will allow for a return of rain showers to the forecast. Slight chances of thunderstorms are forecast for afternoon into evening hours both Thursday and Friday with models indicating low level instability. Daytime temperatures forecast to be near normal Tuesday, below normal Wednesday, slightly above normal Thursday and Friday. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... Low pressure gradually moves farther north of the region through tonight allowing for a gradual entrance of high pressure from the south. High pressure moves offshore Sunday. Expecting mainly VFR conditions through the TAF period. There is a slight chance of a rain shower this afternoon into early evening, mainly north of the NYC terminals. Winds will transition from NW or variable this morning hours to a sea breeze this afternoon for some terminals, changing wind direction to more southerly, while remaining more westerly for others in the afternoon. Wind speeds remain near 5-10 kt much of the TAF period. There will be a time period in the afternoon when winds will be around 10 kt with some gusts up to 15-20 kt. These wind gusts will subside by early evening as winds transition to more westerly to southwesterly flow near 5-8 kt. Once again, winds for some terminals away from NYC will have wind speeds less than 5 kts with variable direction late tonight. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... KJFK and KLGA sea breeze timing could be off by 1-2 hours. KEWR low chance for sea breeze early evening with NW winds prevailing at KTEB. Some gusts 15-20 kt possible in the afternoon for KJFK. OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY... Sunday: VFR. Potential sea breeze enhancement at KJFK late in the afternoon with southerly winds increasing to 15-20 kt. Sunday night: Chance of showers and MVFR. Southerly wind gusts 15-20 kt for some coastal terminals. Monday: Showers and MVFR. Slight chance of thunderstorms afternoon into evening. SE gusts 20-25 kt during the day. SE-S gusts 15-20 kt in the evening. Tuesday: Chance of showers. MVFR possible. Wednesday: Chance of showers. Slight chance of thunderstorms, mainly in the afternoon into early evening. MVFR possible. SW wind gusts 15-20 kt. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Sub-SCA conditions are expected through Sunday. Wind and waves increase Sunday night ahead of the next low pressure system approaching from the west. Gusts upwards of 25-30 kt become possible on the ocean waters as early as 00Z Monday possibly expanding to the sheltered waters during the afternoon. Winds then diminish Monday night but waves on the ocean may be slow to come down. The marine forecast for Tuesday through Wednesday night will be a time period of a relatively weak pressure gradient. This will keep mainly below SCA conditions. Only exception is for Tuesday morning, there is forecast to be SCA level ocean seas east of Fire Island Inlet with otherwise sub-SCA conditions on all other waters. For Tuesday afternoon through Wednesday night, sub-SCA conditions are forecast for all waters. && .HYDROLOGY... Around 1 inch of rainfall is expected for western portions of the CWA Monday afternoon into Monday night. This may result in minor street and poor drainage flooding. While flash flooding is not expected, it can not be completely ruled out. Otherwise, no widespread hydrologic impacts expected through the end of the week. && .TIDES/COASTAL FLOODING... There is a moderate risk of rip currents for Suffolk beaches on Saturday while other beaches at a low risk. All beaches are under a moderate risk Sunday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JM/MW NEAR TERM...MW SHORT TERM...MW LONG TERM...JM AVIATION...JM MARINE...JM/MW HYDROLOGY...JM/MW TIDES/COASTAL FLOODING...