Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 291147 AFDOKX Area Forecast Discussion National Weather Service New York NY 747 AM EDT WED JUN 29 2016 .SYNOPSIS... A cold front will move slowly east across the Tri-State region early today. Weak high pressure builds in tonight through Thursday. High pressure weakens across the region Thursday night into Friday with a cold frontal passage late Friday night into Saturday morning. High pressure then returns behind the front and prevails through early next week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Showers have ended across the region this morning with the cold front now located across central LI and south central CT. Weak high pressure will build in as the cold front pushes off the east coast. It will be dry for the most part today. However, there is the potential for isolated showers and a passing thunderstorm, mainly across Connecticut as a vorticity max moves through. With sea breezes developing, this could provide additional lift for precipitation to occur. Long Island could also see a shower develop along the sea breeze, however, given that it will be situated farther from the approaching vorticity maximum, chances will be less likely here. Therefore, did not mention any showers. Highs today will be seasonable. Humidity levels will drop somewhat across the entire areas, but more so for western areas as drier air move in. A rather humid air mass will still be in place for eastern sections, and this would also help to produce showers and thunderstorms for Connecticut. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... Dry conditions should persist through Thursday with high pressure continuing to build in. Temperatures will continue to be seasonable, with humidity levels continuing to drop into Thursday. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Upper low south of Hudson Bay will rotate through the mean trough and pass through eastern Canada and the Northeast by the close of the weekend. The latter of which will send a cold front across the area late Friday night into Saturday morning, preceded by a round of showers and thunderstorms Friday afternoon and evening along and ahead of a pre-frontal trough. There is the potential for some organization with moderate deep-layer shear and CAPES over 1000 J/KG across much of the area. In addition, models are pointing toward showers developing overnight Thursday as moisture returns around the western periphery of offshore high pressure, interacting with mid level short wave energy. The forecast is slowly trending in this direction. High pressure follows for the weekend into early next week. The 00Z GFS bring a southern branch system close enough to the area Tuesday for showers, however, the ECMWF is suppressed to the south. Subsequent model trends will need to be watched, but for the time will keep the forecast dry. Temperatures continue to remain near seasonable levels throughout the period. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... A cold front will move slowly east across the local area today followed by high pressure tonight and Thursday. Light variable winds with low level moisture will result in areas f IFR/LIFR fog (CIGS and/or VSBY), locally dense until 13z. Fog and stratus clouds will rapidly dissipate by 14z. For today...forecast uncertainties remain with timing the development and movement of sea breezes around 10 kt following NW winds of 5-10 kt between 12z and 17z. Can not rule out an isolated TSTM or widely SCT TSTMs mainly E of NYC near the cold front and possibly along developing sea breeze fronts. 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: Amendments possible for timing the development of sea breezes. Timing within 2 hours. KLGA TAF Comments: Amendments possible for timing the movement of the sea breeze toward KLGA. KEWR TAF Comments: Amendments possible for timing the movement of the sea breeze toward KEWR. The afternoon KEWR haze potential forecast is GREEN...which implies slant range visibility 7SM or greater outside of cloud. KTEB TAF Comments: Amendments not expected. KHPN TAF Comments: Amendments not expected. KISP TAF Comments: Amendments possible for timing the movement of sea breezes within 2 hours. Isolated TSTM possible aft 16z. .OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY... .Thursday through Friday morning...VFR. .Friday afternoon and night...MVFR or IFR conditions possible in showers/tstms. .Saturday and Sunday...VFR. && .MARINE... Patchy fog is possible over all waters through daybreak. Thereafter, visibilities should improve. Conditions should remain below Small Craft Advisory levels in the short term. Winds and seas are forecast to remain below small craft advisory levels from Friday through the holiday weekend. && .HYDROLOGY... No significant rainfall is expected from Wednesday through Friday. Scattered showers and thunderstorms are possible Friday afternoon into early Saturday. Antecedent conditions are very dry, so widespread hydrology issues are not expected. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JP/DW NEAR TERM...JP SHORT TERM...JP LONG TERM...DW AVIATION...GC MARINE...JP/DW HYDROLOGY...JP

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