Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 222001 CCA AFDOKX Area Forecast Discussion...CORRECTED National Weather Service New York NY 401 PM EDT Thu Jun 22 2017 .SYNOPSIS...
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A warm front approaches tonight and passes Friday. A cold front moves across Saturday and behind it another cold front will slowly approach from the north. The second cold front moves in and weakens early next week. This eventually moves farther northeast of the region toward the middle of next week with a strong high pressure area building in from the west thereafter.
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&& .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... Warm and increasingly humid conditions will prevail tonight. Will need to keep an eye on any stratus and fog development, possibly advecting northward from the ocean later tonight. Long Island and southern CT most likely locales. Otherwise, weak shortwaves/vorts in W/SW upper flow, along with an approaching warm front could trigger a few showers/possible thunderstorms overnight. With clouds and southerly flow, warm temps overnight expected with not much disparity across the region. A mos/model blend followed. There is a moderate risk for the development of rip currents at the eastern Suffolk ocean beaches into this evening. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/... A series of weak upper level shortwaves/vorts could trigger a few showers/thunderstorms Friday as a sfc warm front passes in the morning. Capes build, with highest values where they typically are, across the interior away from marine layer. As layer precipitable water values climb to over 2 inches, will mention heavy rainfall with any thunderstorms. Instability wanes somewhat Friday night, but thunder remains a possibility and heavy rain is certainly possible in any convection. In general, expect scattered to numerous coverage, but it will not rain all the time. Warm temps in the 80s during the day can be expected, and 60s to 70 at night, along with high humidity. Again, not much disparity in low temps is expected due to clouds, southerly winds and high humidity in place. && .LONG TERM /SATURDAY THROUGH THURSDAY/... Overall, looking at the large scale, a trough remains in the Northeast this weekend into next week with a pattern change towards more ridging evident towards the end of next week. The area will have the jet stream in the vicinity of the region through early next week. It will be oriented from SW to NE with a max speed of roughly 100-120 kt. At the surface, a cold front will be approaching the region Saturday and moving across from NW to SE through the day. A weak low develops along the front with a sharp mid level shortwave aloft. The front moves farther offshore SE of Long Island Saturday night. A weak pressure pattern sets in place thereafter for Sunday and Sunday night. A cold front approaches and weakens as it moves in early next week. Eventually, building high pressure well west of the region starts to build in mid to late next week. In terms of weather, a wet start to the weekend with showers and a few thunderstorms Saturday. Instability is lower Saturday so left thunderstorm coverage as isolated. Showers are likely. Weather becomes drier from NW to SE during the afternoon with more westerly flow getting established. Mainly dry conditions are expected thereafter. There will be mainly diurnally driven low chances for showers and thunderstorms Sunday through early next week, but expect majority of the region to remain dry. Temperatures a little above normal Saturday but otherwise right near normal values for the rest of the long term period. && .AVIATION /20Z THURSDAY THROUGH TUESDAY/... Weak high pressure remains over the area into this evening. A warm front crosses later tonight. VFR with typical sea breeze wind directions at 10-15 kt. NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/www.weather.gov/zny/n90 KJFK TAF Comments: No unscheduled amendments expected. KLGA TAF Comments: No unscheduled amendments expected. KEWR TAF Comments: Moderate confidence that SE winds prevail through at least 21z. Chance that winds waver between SE and SW for a period of 2-3 hours thereafter. Best guess is they remain SE for most if not all of the time from 21-00z. KTEB TAF Comments: No unscheduled amendments expected. KHPN TAF Comments: No unscheduled amendments expected. KISP TAF Comments: No unscheduled amendments expected. .OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY... .Friday-Friday Night...MVFR or lower in shra/tsra. S/SW winds G20- 25KT possible Friday afternoon. IFR of lower conditions possible in stratus/fog for eastern terminals Friday Night. .Saturday...MVFR or lower possible in shra/tsra. S/SW winds. .Saturday night-Sunday Night...VFR. NW winds...becoming W/SW. .Monday...VFR. Chance of afternoon shra/tsra. S/SW winds. .Tuesday...VFR. && .MARINE... Southerly winds tonight remain well below SCA criteria, but do expect these southerly winds to increase by Friday afternoon and into the evening. At this time, will issue a SCa for the ocean waters for winds 20 to 25 kt, and building seas in the 5 to 6 foot range. The remainder of the waters should remain below SCA criteria. The other hazards for mariners will be showers/thunderstorms, and reduced visibilities in fog. In terms of winds, the pressure gradient will be weak enough through the long term marine forecast period (Saturday through Tuesday) to keep winds below SCA criteria. However, the seas on the ocean will probably still have southerly swell contributing to higher seas of 5- 6 feet on the ocean that are forecast to last through early Sunday. The 5-6 foot seas will last through the day Sunday for the ocean east of Fire Island inlet. Seas are forecast to go below 5 feet for all ocean waters Sunday night through Tuesday. Non-ocean waters stay below 5 feet the entire long term marine forecast period. && .HYDROLOGY... There is the potential for heavy rain late Friday into Sat as the remnants of Cindy move through. At this time expect at least flood advisories to be issued. It is too early to tell if flash flooding will occur due to the lack of instability. This potential could be added to the HWO in subsequent forecasts. Otherwise, no other hydrologic concerns. && .TIDES/COASTAL FLOODING... Astronomical tides are running very high, especially during the evening high tide cycles through Saturday. Less than 1 ft of surge is needed during these evening high tide cycles for minor flooding, and in some cases less then 1/2 ft. The expected S/SW flow is not favorable for surge, but a background anomaly will likely be enough for minor coastal flooding of the most vulnerable coastal locales along the south shore bays of Western Long Island, along Jamaica Bay, and along western Long Island Sound during this time. && .EQUIPMENT... KOKX weather radar is scheduled for maintenance starting Friday June 23rd for a period of 3 days. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory from noon Friday to 6 AM EDT Saturday for ANZ350-353-355. && $$ SYNOPSIS...JM/PW NEAR TERM...PW SHORT TERM...PW LONG TERM...JM AVIATION...JC MARINE...JM/PW HYDROLOGY...JM/PW TIDES/COASTAL FLOODING... EQUIPMENT...

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