Area Forecast Discussion
Issued by NWS Upton, NY

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
854 FXUS61 KOKX 250546 AFDOKX Area Forecast Discussion National Weather Service New York NY 146 AM EDT WED MAY 25 2016 .SYNOPSIS... High pressure builds to the south through Wednesday night. A cold front moves through on Thursday. High pressure will then dominate through Saturday night as a series of weak upper level disturbances move across. A cold front will move through on Sunday. High pressure will build in its wake across New England Sunday afternoon and night, then pass offshore Monday, allowing a broad area of low pressure to begin approaching from the south later Monday into Tuesday. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Measurable precipitation has come to an end, so have removed all pops greater than 14 from the area for the remainder of the night. Main issue overnight will be patchy fog...mainly over coastal CT and eastern Long Island, as well as possibly portions of the Lower Hudson Valley. For now, appears will only be locally dense, so will address with a special weather statement. However, will continue to monitor, as cannot rule out the dense fog becoming more widespread and needing to go with a short fused Dense Fog Advisory for all/part of this area for early this morning. Ridging aloft builds in overnight, with increasing subsidence allowing for cloud cover to diminish. Lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS...with minor adjustments downward for normally cooler locations. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/... For Today, ridging aloft continues with high pressure establishing itself southwest of the region. A very warm day is expected with highs around 15 degrees above normal on average...cooler at the immediate eastern shorelines with partial sea breeze influences. Overall though less marine influence with the more westerly flow. For Wednesday Night and Thursday, aloft there will be continued ridging. At the surface, a cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... summer like warmth will continue through the first half of the weekend as longwave upper ridging moves across. Shortwave disturbances will however be able to move through the longwave ridge and bring chances for late day convection mainly from NYC north/west both Friday and Saturday. GFS seems too quick to do so on Thursday as well, and think any convection that day will be isolated in nature and confined to well NW of NYC. High temperatures both Thu/Fri will be well into the 80s in most places, and some isolated lower 90s are not out of the question somewhere in urban NE NJ, in the valleys of Orange County, or the interior lower CT river valley. Lows will range mostly from the mid 50s to the mid 60s. The ridge then weakens across New England in response to a sharp northern stream disturbance moving across eastern Canada, pushing a back door cold front through on Sunday as a surface high builds across New England. Forecast details become less certain from Sunday onward, and will be dependent on how far south the front sinks. Forecast temperatures could be at least several degrees cooler and chances for rain lower if the front does push farther south. Leaning more toward the ECMWF idea of more of a glancing blow from this cooler air mass for now. As we go into Monday night and Tuesday, we should start dealing with influx of Atlantic moisture well north of a subtropical or tropical weather system now just beginning to organize near and northeast of the Bahamas, and forecast by global models to head toward the Southeast coast. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
High pressure builds in today. VFR, except reduced vsbys in BR/FG at Hudson Valley and CT terminals through 12z. Light/calm winds pre-dawn bcmg West 5 to 10 kt in the morning, increasing 9-14 kt in the afternoon and backing slightly, more so at the coastal terminals. Gusts 15-19 kt. .OUTLOOK FOR 06Z Thursday through Sunday... .Wednesday night through Thursday...VFR. .Thursday night through Friday morning...Mainly VFR but sub-VFR possible in showers/evening thunderstorms. .Friday-Saturday...MVFR possible in afternoon/evening tstms. .Sunday...Mainly VFR, but sub-VFR in showers possible NW of NYC.
-- End Changed Discussion --
&& .MARINE... Minor changes were made with this update to reflect the latest trends in observations and guidance. The forecast appears on track. There is a chance for patchy dense fog over mainly the near shore waters overnight. Will address with a marine weather statement if it occurs. A weak pressure gradient force will be across the waters through Sunday morning, allowing for forecast winds and seas to stay below SCA criteria. Minimal SCA conditions mainly in the form of higher ocean seas may be possible Sunday afternoon and night as easterly flow increases following a back door cold frontal passage. && .HYDROLOGY... Mainly, if not entirely dry, through Thursday night. Local minor flood impacts from heavier showers/tstms are possible both late day Friday and Saturday, possibly still well inland well N/W of NYC on Sunday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ AVIATION...JC is the U.S. government's official web portal to all federal, state and local government web resources and services.