Area Forecast Discussion
Issued by NWS Upton, NY

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422 FXUS61 KOKX 290738 AFDOKX Area Forecast Discussion National Weather Service New York NY 338 AM EDT Thu Jun 29 2017 .SYNOPSIS...
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High pressure settles over the western Atlantic today as a warm front passes well to the north through tonight. The offshore high will dominate the weather on Friday into Saturday. A cold front will slowly approach over the weekend and pass by late Sunday. High pressure will then build in from the northwest through the beginning of next week.
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&& .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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Middle and upper level cloud cover will continue to stream across the region this morning. This moisture, largely resulting from weakening convective complexes over the Great Lakes and upper midwest, is spilling over weak ridging aloft. The day will likely start out mostly cloudy, but expect these clouds to thin and scatter out heading into the afternoon with just some scattered cumulus and cirrus clouds. High pressure moves over the western Atlantic with a steadily tightening pressure gradient into the afternoon. Increasing S-SSW flow will result with sustained winds near the coast 15-25 mph with gusts 30-35 mph. The strongest winds look to reside across Long Island and southeastern Connecticut this afternoon. Temperatures are a bit tricky today due to cloud cover to start the day and then increasing onshore flow this afternoon. Highs across the NYC metro, NE NJ, and Lower Hudson Valley will likely reach the middle and upper 80s with Long Island and southern Connecticut in the upper 70s to lower 80s. If stronger southerly flow takes shape sooner than expected, much of Long Island and coastal Connecticut may not make it out of the 70s. Dangerous rip currents are expected at the ocean beaches, particularly in the afternoon and evening. A high rip current risk remains in effect.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
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The main story for tonight will be increasing humidity levels and much warmer temperatures than recent nights. A wave of low pressure moves into the Great Lakes region with its associated warm front settling across northern New England. Other than some weak short wave energy, there is not much in the way of support for convection tonight. Have confined slight chance pops to the interior where a bit more elevated instability is progged to reside, but think the night should largely be dry. Low temperatures in the upper 60s to near 70 are forecast. Ridging builds over the western Atlantic on Friday. Temperatures and humidity levels continue to increase with temperatures approaching 90 degrees in the NYC metro and NE NJ and upper 80s across the interior. Onshore flow will hold readings down into the upper 70s on the immediate shore and lower 80s just inland across Long Island and southern Connecticut. Gusty S-SSW winds expected again, but not as strong as Thursday, mainly 20-25 mph near the coast. Diurnal heating is the only source for any convection with chance PoPs confided to the NW interior.
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&& .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
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An upr low over the Canadian prairie Fri ngt will drop sewd and reach Lake Superior by Sun ngt. This will begin to carve out sw flow aloft thru the period across the fcst area. Under this flow regime, the best chance for rain is generally across the interior, or even just nw of the fcst area, until significant forcing reaches the region. Because of this, pops were limited to 30 percent thru the weekend. The wild card will be residual convective complexes which would be capable of kicking off a round of rain and tstms. It will be warm and humid over the weekend with a blend of model data used for temps. Although the mainly sly flow will limit temps, particularly across Long Island and CT, it will keep the humidity up until a wly component is added by Sun ngt. The only reason fog was not included attm is because the winds may not fall off sufficiently overnight. Otherwise, the sly flow will keep the ocean choppy and result in a continued rip risk thru at least Sat. The upr trof, based on the 00z ECMWF and GFS data, comes thru Mon and Tue. This will provide some dpva and help to steepen lapse rates, however it appears the deepest moisture will have been shunted offshore by this point, allowing for only isold-sct coverage of any shwrs and tstms. Pops were limited to 30 percent Mon and Tue because of this. Wed looks to be between the departing upr trof and the next approaching system. The fcst has been kept dry as a result.
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&& .AVIATION /08Z THURSDAY THROUGH MONDAY/... High pressure slowly drifts offshore through Thursday night. Mainly VFR conditions expected. Winds will be SW 5-10 kt for city terminals and KISP tonight into early Thursday with otherwise light and variable winds. S-SW winds increase to 10-20 kt with gusts mostly around 20-25 kt Thursday into Thursday evening with some peak gusts to 30kt for early evening. Strongest and most southerly winds expected at KJFK and KLGA. Winds decrease late Thursday night to 10-15 kt with gusts to 20 kt. .OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY... .Friday-Saturday morning...Mainly VFR. Chance of shra/tstm north and west Friday afternoon/evening. SW gusts 25 kt Fri pm. .Saturday afternoon-Sunday...Chance showers/thunderstorms with sub-VFR conditions. SW gusts 20-25 kt Sat pm. .Monday...VFR. && .MARINE...
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Increasing S-SSW flow today as pressure gradient tightens with high pressure moving offshore. SCA continues on all waters starting this morning and running through midnight on near shore waters and through Friday on the ocean. Winds will gust to 25-30 kt on all waters, especially this afternoon. Gusts should stay below 34 kt, but it would not be out of the question for a few isolated gusts to reach 34 kt. Ocean seas will quickly build through the day, reaching 5 to 6 ft this evening. Winds on the ocean may briefly fall below 25 kt late tonight, but should once again reach around 25 kt on Friday. Ocean seas will continue to run 5-6 ft through Friday. Winds and seas will remain at sca lvls on the ocean Fri ngt thru Sat ngt before subsiding on Sun. Elsewhere, winds appear to remain just blw sca lvls attm. Winds and seas are progged to stay blw sca lvls Mon and Tue.
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&& .HYDROLOGY... No hydrologic impacts expected into the middle of next week. && .EQUIPMENT... Observations from KFRG (Farmingdale, NY) may still be sporadic due to a communication line outage. Return to full service time is still unknown. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...High Rip Current Risk from 8 AM EDT this morning through this evening for NYZ075-080-081-178-179. NJ...None. MARINE...Small Craft Advisory from noon today to midnight EDT tonight for ANZ330-335-338-340-345. Small Craft Advisory from noon today to 6 PM EDT Friday for ANZ350-353-355. && $$ SYNOPSIS...JMC/DS NEAR TERM...DS SHORT TERM...DS LONG TERM...JMC AVIATION...JM MARINE...JMC/DS HYDROLOGY...JMC/DS EQUIPMENT...

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