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 220544 AFDOKX Area Forecast Discussion National Weather Service New York NY 1244 AM EST Tue Jan 22 2019 .SYNOPSIS... Strong high pressure will build in through Tuesday, then pass east Tuesday night. A frontal system will impact the area Wednesday into Thursday, with brief high pressure following for late week. Another frontal system will be possible late in the weekend into early next week. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Gusty NW winds will be slow to diminish tonight as strong high pressure builds east from the Ohio Valley and low pressure tracks across the Canadian Maritimes. A few gusts up to 45 mph will still be possible through about midnight near the coast. Skies have cleared across the area with the departure of the upper trough. Temps should bottom out at 0 to 5 below well inland, and in the single digits to lower teens elsewhere. Could still be a few areas well inland in the higher elevations where wind chills could hit -15, otherwise they should be in the -5 to -10 range. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/... Wind chills should generally be 0 to -10 around day break Tuesday. High pressure will remain in control on Tuesday with ridging aloft and mostly sunny skies, then slide east Tue night. As the upper ridge slides east, there could be a period of partly/mostly cloudy skies via WAA aloft. Temps will moderate into the 20s for highs on Tue, then remain in the 20s in NYC and drop to the teens inland. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... Main system of concern will impact the area Wednesday into Thursday, as a series of short waves rotate around a long wave trough expected to develop into much of the eastern U.S. Strengthening winds between the departing deep layer ridge and deepening trough will allow rapid warm advection into Wednesday. Although a wintry mix may be possible at the onset, general consensus shows temperatures quickly rising above freezing into the afternoon. There remains significant differences with the expected track and intensity of the surface low. The Canadian has been fairly consistent in showing a more western track, which the 12Z European has come more into line with. The more western track would allow a warmer air mass, along with the potential for gustier winds. Similarly, each consecutive run of the NAM has trended farther inland, while the GFS has subtly shifted farther north and west. Given these trends, and the superior performance of the Canadian and European with the last system, have trended slightly warmer/inland with the system. At the moment, the main impact will be the potential for heavy rainfall as strong unidirectional flow will be oriented parallel to the frontal boundary. With strong moisture advection from the Gulf, PW will rise to above 90th percentile values for time of year. Additionally, the low will be slow to exit the area. Trends will need to be monitored closely. For now, trended more towards WPC guidance, with a general 1-2 inches across the area, closer to deterministic values and the GEFS ensemble mean. After the system departs, gusty northwest flow develops. Another strong vorticity maximum is progged to move through the region Friday, leading to the potential for brief snow showers in developing stratocu, though accumulations will be minimal. Confidence thereafter significantly decreases, with major differences in model solutions, though with the continued presence of the upper trough to the west and short waves that may rotate through, expect an unsettled pattern to continue into at least early next week. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... Canadian high pressure builds over the area today, then slides offshore into tonight. VFR through the TAF period. NW winds diminish this morning. Gusts should abate throughout by around 7-9Z as speeds decrease to around 10-15KT. Speeds continue to slowly decrease to less than 10 kt, at all terminals, as winds gradually back to the WNW-W by early-mid afternoon. Winds become light and variable areawide by late afternoon/early evening and remain so through at least 6Z Wednesday. .OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY... .Late tonight-Wednesday morning...VFR. SW winds G25-35KT possible at eastern terminals and LLWS possible at western terminals. .Wednesday afternoon...MVFR or lower developing in rain, possibly starting as a wintry mix at northern terminals. LLWS possible. .Wednesday night-Thursday night...IFR or lower likely with rain, precipitation may change to snow before ending. Becoming VFR late Thursday night. LLWS possible Wednesday night. N-NW winds G15-25KT possible Thursday afternoon/night. .Friday-Friday night...Most likely VFR, with MVFR possible in any snow showers. NW winds G15-20KT possible Friday. .Saturday...VFR. && .MARINE... Gale warning continues for all waters with wind gusts 35-40 kt through the overnight and then for the ocean waters east of Moriches Inlet through the morning. Conds ramp down to sub-SCA on all waters by late morning. This lull will be short lived as S flow increases to 20 kt by late Tue night and pushes ocean seas back up to 5 ft. Winds/seas should increase Wed into Thu as the next low pressure system impacts the waters. Gales will be possible on the ocean waters, especially late Wednesday into Thursday morning. The system then departs late Thursday into Thursday night, with at least SCA gusts possible on all waters. High pressure then only briefly builds by late week into the first half of the weekend, with ocean seas slowly subsiding, but likely remaining above 5 ft. && .HYDROLOGY... A low pressure system Wednesday into Thursday may bring 1 to 2 inches of rainfall to the area, though timing and placement of any potential impacts remains uncertain at this time. && .TIDES/COASTAL FLOODING... Low Water Advisory through the next low tide cycle late tonight for the coastlines of the ocean waters west of Moriches Inlet into NY Harbor and on the western Sound. Water levels will reach 2 to 2.5 ft below MLLW. Water levels should remain above low waters thresholds farther east. && .EQUIPMENT... NYC Central Park winds are out of service until further notice. Loss of data is due to a severed cable. Parts are on order. NYC NOAA Weather Radio Station KWO35 (162.55 MHz) will remain off the air for an extended period of time. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...Low Water Advisory until 7 AM EST this morning for ANZ338-345- 353-355. Freezing Spray Advisory until 6 AM EST early this morning for ANZ335-338. Gale Warning until 6 AM EST early this morning for ANZ330-335- 338-340-345-353-355. Freezing Spray Advisory until noon EST today for ANZ330-340- 350-353-355. Low Water Advisory from 4 AM to 7 AM EST this morning for ANZ335. Gale Warning until 10 AM EST this morning for ANZ350. && $$ SYNOPSIS...MD/Goodman NEAR TERM...Goodman/DW SHORT TERM...Goodman LONG TERM...MD AVIATION...Maloit MARINE...MD/Goodman/DW HYDROLOGY...MD/Goodman TIDES/COASTAL FLOODING... EQUIPMENT... is the U.S. government's official web portal to all federal, state and local government web resources and services.