Area Forecast Discussion
Issued by NWS Upton, NY

Current Version | Previous Version | Text Only | 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 191435 AFDOKX Area Forecast Discussion National Weather Service New York NY 1035 AM EDT Sat Aug 19 2017 .SYNOPSIS... One cold front will pass east of Long Island this morning, while another passes through tonight. High pressure will follow from Sunday through Tuesday. A frontal system will move across from Wednesday into Wednesday night, followed again by high pressure. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Shortwave trough aloft over the Great Lakes this morning will pivot toward the region late today. A weak surface trough will linger today, with a cold front approaching from the west for tonight. A much drier air mass in the low/mid levels will advect/mix down today. With shortwave energy still well west and mid-level warming, forcing and instability will be limited today. Would mainly expect some diurnal Cu along and north of afternoon surface sea breeze boundaries. The mostly sunny conditions and warm temps aloft will allow temps to quickly rise well into the 80s today, around 90 NYC/NJ metro. Heat indices will run close to air temperatures. Residual southerly swells of 3-4 ft @ 6-7 sec period this morning favor a high rip current risk for the eastern Long Island ocean beaches, and a moderate risk farther west. These swells will continue to slowly subside into this evening. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... Vigorous shortwave trough approaches this evening and crosses the region tonight. At the surface, a weak cold front crosses the region this evening. High-res models indicating some organized convection developing/tracking across central PA/NY late this afternoon along this front, but expectation is that this activity quickly weakens as it approaches and crosses into the NW hills this evening due to lack of instability. Elsewhere, a low chance for an isolated shower overnight with shortwave/frontal passage. Zonal upper flow ensues for Sun into Mon. At the surface...high pressure builds in from the west Sunday into Sunday Night, and then gradually translates to the south and southeast Sunday night. The result will be a sunny, comfortably dry, and seasonably warm day on Sunday. As the high sinks south and east, heat and humidity will build build into the region Monday into Tuesday. Highs will generally be well into the 80s to lower 90s on Monday, and possibly lower to mid 90s for Tuesday. Models are indicating potential for isolated diurnal convection on Tuesday as instability increases and convectively induced vort energy rotates around the upper ridge. Low predictability at this point. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... Decent model agreement with shortwave energy digging into the Great lakes Tue into Tue Night and then towards the NE US on Wed. An associated frontal system will bring the next chance for organized shower and tstm activity late Tue into Wed. A significant cool down then looks to follow for the end of the week. The models have been very consistent with this signal, although the exact magnitude of the cold airmass remains in question. It would not be totally surprising to see some lows in the furthest outlying areas touch the upr 40s next weekend. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/... A secondary cold front will move across the region tonight, perhaps bringing an isolated shower to KSWF. This will be followed by high pressure. VFR through the TAF period. W-NW flow under 10 kt will continue this morning before winds back to the SW this afternoon. A few gusts to around 15kt are possible at the city terminals late this afternoon into early evening. Winds subside again tonight, becoming variable in direction but overall exhibiting a west to southwest flow for city and coastal terminals. .OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY... .Sunday-Monday night...VFR. .Tuesday-Tuesday night...A chance of showers and thunderstorms with MVFR or lower conditions possible,otherwise VFR. SW gusts to 15-20 kt late afternoon and at night. .Wednesday...A chance of showers and thunderstorms with MVFR possible. SW gusts 15-20 kt. && .MARINE... SCA has been cancelled as ocean season continue to subside. Winds and seas will increase ahead of a cold frontal passage late Tuesday into Wednesday. Ocean seas may reach advy levels Tuesday night, and continue in southerly swells into Wed night. && .HYDROLOGY... Impacts from potential showers and thunderstorms Tuesday into Wednesday are uncertain at this point. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...High Rip Current Risk until 8 PM EDT this evening for NYZ080- 081. NJ...None. MARINE...None. && $$ SYNOPSIS...Goodman/NV NEAR TERM...Goodman/NV SHORT TERM...NV LONG TERM...JMC/NV AVIATION...FEB/JM MARINE...Goodman/NV HYDROLOGY...NV is the U.S. government's official web portal to all federal, state and local government web resources and services.