Area Forecast Discussion
Issued by NWS Upton, NY

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753 FXUS61 KOKX 161822 AFDOKX Area Forecast Discussion National Weather Service New York NY 122 PM EST Sat Dec 16 2017 .SYNOPSIS... Weak low pressure passes to the north today bringing a cold front south of the region. High pressure builds in for tonight and Sunday. Then a series of lows will pass through the area through mid week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Increasing clouds are expected through the remainder of the day as the next vorticity maximum passes across New England and a weak cold front approach from the NW. The cold front will pass through from north to south into the evening. Some snow showers are possible this afternoon across the interior. Drier low levels across the region should prevent any widespread activity, but some of these snow showers could translate towards to the coast by early this evening as the cold front moves through. Do not anticipate any accumulation other than possible a dusting if a snow shower does occur. Breezy westerly winds are forecast today with gusts 20-25 mph at times. High temperatures will range from the lower and middle 30s inland to the upper 30s near the coast. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/... A few flurries may be lingering into the early evening hours if the cold front is slower to push through. At this time will keep the evening dry. Height rise tonight through Sunday as the flow becomes more zonal. A dampening shortwave will be moving into the weak upper ridge late Sunday and Sunday night, and pass through Sunday night. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... A weakening shortwave passes through Sunday night into Monday. Have lowered the probabilities slightly as the shortwave is weakening and flat, with little moisture. Warmer air will be pushing into the region, and as the warm air lifts north of the cold surface air a period of freezing rain, some ice pellets and snow will be possible. Too early for specific details on this light precip event. Thereafter, models in fairly good agreement with the broad bu shallow northern stream trough approaching the region on Tuesday and sliding through during the midweek. At the surface, the primary low pressure system rides through Quebec/Ontario with trailing cold front approaching the region Tuesday Night. Overall, appears to be mainly a light qpf event for the Monday night into Tuesday evening period, due to limited interaction between northern and southern stream. Thermal profile suggests precip would be mainly liquid, but could be dealing with freezing rain across interior Monday night as cold air typically has a tough time scouring our in this setup. Upper trough swings through the NE Tue Night into Wed with a glancing shot of modifying arctic air in the wake of the cold front for Wed/Thu. Upper flow flattens and even becomes a bit ridged for Thursday ahead of the next northern stream trough digging into the Upper Plains, which should allow for a moderation in temps ahead of next potential frontal system. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/...
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A cold frontal passage occurs this evening. Ceilings around 3500 ft can generally be expected through the TAF period for the city terminals, coastal Connecticut and Long Island. To the north however, there is a higher probability for ceilings to settle around 3000 ft for this afternoon and evening. MVFR has therefore been forecast for those areas. There is a chance for snow showers through approximately 00Z. VCSH have been included in the TAFs, with coverage expected to be mainly isolated at this time. Winds in the 250-270 true range will veer to the northwest behind the cold front tonight. The winds will continue to veer to the north on Sunday. .OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY... .Rest of Sunday...IFR possible overnight with snow or a light wintry mix possible. Variable wind direction with speeds below 10 kt. .Monday...Light rain possible along the coast in the morning, with a light wintry mix possible elsewhere. Becoming VFR. Westerly flow developing. .Tuesday...Areas of MVFR possible with southwest flow. .Wednesday...VFR with northwest flow 20-25 kt. .Thursday...VFR with light winds becoming southerly.
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&& .MARINE... Gusty small craft winds are likely across all the forecast waters today into early this evening as a rather tight pressure gradient moves through the waters as low pressure moves into the Atlantic and high pressure builds to the west. Gusty winds may linger into this evening on the ocean waters. Ocean seas may remain around small craft levels into the first part of tonight. So, the advisory remains into this evening on the ocean. The next chance for SCA conditions will be late Tuesday/Tue eve ahead of approaching cold front, but higher likelihood of widespread SCA Tuesday Night through Wednesday night with tight pressure gradient and strong caa in wake of cold front. Gales are possible during this time frame. && .HYDROLOGY... No significant hydrologic impacts expected. && .EQUIPMENT... NYC NOAA Weather Radio Station KWO-35 (162.55 MHz) is off the air for an extended period of time. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory until 7 PM EST this evening for ANZ330- 335-338-340-345. Small Craft Advisory until 1 AM EST Sunday for ANZ350-353-355. && $$ SYNOPSIS...24/MET NEAR TERM...DS/MET SHORT TERM...MET LONG TERM...NV AVIATION...12 MARINE...24/MET HYDROLOGY...24/MET EQUIPMENT...

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