Area Forecast Discussion
Issued by NWS Upton, NY

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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. --
000 FXUS61 KOKX 250159 AFDOKX Area Forecast Discussion National Weather Service New York NY 959 PM EDT TUE MAY 24 2016 .SYNOPSIS...
-- Changed Discussion --
Low pressure departs to the northeast as high pressure builds to the south on Wednesday. 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.
-- End Changed Discussion --
&& .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
-- Changed Discussion --
The forecast is generally on track. persistent showers continue to track down from new england...so have added chc pops for a few more hours as a weakening trend is noted on radar as well as in the hrrr. dry weather should return by midnight with decreasing clouds overnight. have also added patchy fog to ct coastal areas and ern long island overnight with light winds and high moisture content at the sfc. Otherwise...minor adjustments made to hourly t/td. The region will be behind a weak surface trough. The upper level low and associated cold pool aloft shift east of the region. This will increase subsidence with ridging aloft. The lows were a blend of 1/3 MET, 1/3 MAV and 1/3 12z GMOS. With lighter winds across the interior, min temperatures were further lowered by a degree.
-- End Changed Discussion --
&& .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... For Wednesday, the surface trough will be just east of the region. This will allow for westerly flow to continue. Aloft...ridging 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, aloft there will be continued ridging. At the surface, the pressure gradient will become weak with high pressure becoming weaker and translating farther south into the open Atlantic. A parent low moves into the Canadian Maritimes but will be filling in with increasing central pressure...essentially weakening. The associated cold front moves through by early Thursday but will be weakening as well. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Summerlike 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 /02Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
Low pressure departs to the northeast as high pressure builds to the south overnight and Wednesday. Mid and high clouds give way to clear skies overnight and through the day Wednesday. However, lingering stratus will take a little longer to scour out for eastern terminals such as KGON. In addition, patchy fog will likely develop after midnight for a few outlying terminals. MVFR or IFR vsbys are possible. After 12z, any fog lifts. Winds will be light overnight. West winds 5 to 10 kts in the morning Wednesday will increase to 9 to 13 kts in the afternoon. A few gusts are possible in the 15 to 20 kt range. Winds may back around to the s/sw at KJFK, and CT terminals in the afternoon with seabreeze influence. .OUTLOOK FOR 00Z 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... A weak pressure gradient force will be across the waters through Wednesday Night, allowing for forecast winds and seas to stay below SCA criteria. The only hazard across the forecast waters, mainly the western forecast waters, will be isolated to scattered thunderstorms this afternoon into early this evening with potential for gusty winds, heavy rain and small hail. Otherwise no hazardous conditions are expected. 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...
-- Changed Discussion --
light pcpn amounts (less than 1/10 inch) in any remaining showers this eve. 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.
-- End Changed Discussion --
&& .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.