Sandy Hook NJ to Fire Island Inlet NY out 20 NM Marine Forecast
|Tonight...S Winds 15 To 20 Kt With Gusts Up To 25 Kt, Increasing To 20 To 25 Kt With Gusts Up To 30 Kt After Midnight. Seas 4 To 6 Ft, Building To 5 To 8 Ft After Midnight. Chance Of Rain Late This Evening And Early Morning. Rain Late With Vsby 1 To 3 Nm.|
|Thu...S Winds 25 To 30 Kt, Becoming W In The Afternoon. Gusts Up To 40 Kt. Seas 8 To 13 Ft. Rain In The Morning, Then Showers In The Afternoon. Vsby 1 To 3 Nm.|
|Thu Night...Nw Winds 15 To 20 Kt, Becoming W 10 To 15 Kt After Midnight. Gusts Up To 30 Kt. Seas Subsiding To 6 To 9 Ft, Then To 5 To 7 Ft After Midnight.|
|Fri...W Winds 15 To 20 Kt With Gusts Up To 30 Kt. Seas 5 To 7 Ft.|
|Fri Night...Nw Winds 15 To 20 Kt With Gusts Up To 30 Kt, Becoming W 10 To 15 Kt With Gusts Up To 20 Kt After Midnight. Seas 4 To 7 Ft.|
|Sat...W Winds 5 To 10 Kt, Becoming Sw In The Afternoon. Seas Subsiding To 2 To 4 Ft.|
|Sat Night...S Winds Around 5 Kt, Increasing To 10 To 15 Kt After Midnight. Seas 2 To 3 Ft.|
|Sun...Sw Winds 10 To 15 Kt. Seas 2 To 4 Ft.|
|Sun Night...W Winds Around 15 Kt. Seas 3 To 5 Ft.|
|Mon...Nw Winds 10 To 15 Kt, Becoming N In The Afternoon. Seas 2 To 4 Ft.|
|Mon Night...E Winds 10 To 15 Kt. Seas 2 To 3 Ft, Building To 3 To 5 Ft After Midnight. Chance Of Snow After Midnight With Vsby 1 To 3 Nm.|
|Area Forecast Discussion|
National Weather Service New York NY
416pm EST Wednesday Jan 23 2019
Synopsis: A cold front approaches from the west tonight, with a wave of low pressure riding along it. The front and low cross the area on Thursday, followed by high pressure building in from Thursday night. into Saturday. A cold front will then approach from the Great Lakes on Sunday, and pass through Sunday night. Low pressure moving out of the Plains States on Monday will approach Monday night into Tuesday, then pass through along with a cold front Tuesday night into Wednesday morning.
Near Term - Until 6am Thursday Morning
A deep layered ridge continues to slowly exit to the east tonight. As it does so, it will allow for a mainly light rain to build in from west to east. However, the rain should increase in intensity over mainly NE NJ/NYC/Lower Hudson Valley and parts of SW CT late tonight in response to increasing isentropic lift.
Lows tonight should be around 15-20 degrees above normal.
Short Term - 6am Thursday Morning Through Thursday Night
A northern stream 700-500 hPa shortwave trough crosses the area on Thursday. Associated forcing, coupled with the region being in the right rear quadrant of a 160+ kt 300 hPa jet and a 80-105kt 950-850 hPa jet passing near/over southern portions of the area, and increasing isentropic lift, will have ample forcing to produce moderate to locally heavy rainfall into Thursday afternoon. In addition Showalter indices are progged down to around 2 to -2 ahead of the surface cold front mid Thursday morning-mid Thursday afternoon, so have a slight chance of Thunder with locally heavy rainfall as well. As a result have continued the flash flood watch for the entire CWA. Refer to the hydrology section of the AFD for details on impacts and amounts.
In addition to the locally heavy rainfall, with that strong of a low level jet in the vicinity of the region, even with a strong low level inversion there is the potential for sustained winds and possibly isolated gusts to wind advisory criteria for coastal areas. As a result have issued a wind advisory for Long Island/NYC/coastal S CT/Hudson and S Westchester Counties from 14-23Z (so could see sustained winds of 30-35mph and/or gusts up around 50 mph). Outside the advisory area isolated gusts of 30-45mph are possible on Thursday.
Furthermore, with low level instability forecast over the area (aforementioned Showalter indices around 2 to -2), there is the potential for isolated strong convection, which could organize itself as a fine line ahead of the cold front. If this occurs, there is the potential for gusts to severe limits (at least 58 mph). If this occurs, this will be addressed by a severe thunderstorm warning. This could occur anywhere in the CWA (from W to E) from mid morning-mid afternoon on Thursday.
Highs on Thursday should be around 15-20 degrees above normal and lows Thursday night around a few degrees above normal. With decreasing winds through the night, wind chills will only run around 10 degrees below the air temperature Thursday night, and should bottom out from the mid teens-around 20 across most of the area late Thursday night
Long Term - Friday Through Wednesday
Medium range guidance in general agreement on the big picture, with a broad upper trough dominating through the weekend, then as this trough lifts out into eastern Canada, transition to Eastern ridging early/mid next week as the polar vortex drops S into central Canada and the northern Plains. This will lead to a gradual trend to below normal temps into the weekend, with low temps in the teens/20s Fri night/Sat night, and highs on Sat from the mid 20s to lower 30s. Temps warm up briefly on Sunday ahead of a weak northern stream frontal system, with the cold air returning Monday into Monday night.
Low pressure moving out of the Plains states will bring another frontal system toward the area late Monday night into Tue. Partial thicknesses and surface temps/dewpoints support idea of precipitation beginning as snow, then transitioning to mixed wintry precipitation throughout on Tue, then to rain along the coast and possibly inland Tuesday afternoon and night. A cold front passing through Tuesday night should bring a lasting trend toward colder weather to end the month and going into February as longer range guidance shows the polar vortex dropping into the Plains and eastern North America. However, if recent trends with other weather systems hold for mid next week, would expect a warmer scenario for Tuesday into Tuesday night, and perhaps a slower progression of the cold front Tuesday night into Wed.
Small craft conditions tonight, give way to gales on all waters on Thursday. Small Craft Advisory conditions return again by Thursday night.It should be noted, that there is the low end chance for a convective line to produce gusts to around/above 50 kt on Thursday out ahead of the cold front. Special Marine Warnings will be issued for any gusts expected above gale force due to convection.
Small Craft Advisory conds should already be ongoing Fri morning, then spread to the remaining waters Fri afternoon/eve as high pressure begins to build in. Lingering 5+ ft seas expected on the ocean late Fri night into Sat morning.
Small Craft Advisory conds also expected late Sunday night into Monday on at least the eastern ocean/sound/bays after a cold frontal passage. Some 5-ft seas may persist into Monday night as low level flow veers clockwise to onshore as high pressure passe to the north.
1.25 to 2.25 inches of rain is forecast through Thursday, with locally higher amounts possible. Most of this will fall during Thursday morning into early afternoon. Urban and poor drainage flooding is therefore possible for Thursday, as well as small stream and flashy river flooding. Larger streams and main stem rivers should remain below flood stage.
Quantitative Precipitation Forecast up to 1/2 inch liquid equivalent possible late Monday night into early Wed
Tides / Coastal Flooding
Strong southerly winds ahead of an approaching strong cold front, as well as southerly swells building to 15 ft, will present a threat for minor coastal flooding during the times of high tide Thursday morning into afternoon.
With the recent full moon, tidal departures of only 1 to 1 1/2, locally 2- 2/12 ft, are needed for minor coastal flooding. Have leaned towards high end of Stevens guidance based on current water levels currently running on the high end of the surge guidance, and past performance this season. ETSS is showing a negative surge for Thu high tides, which seems unlikely.
Based on above surge and incoming swells, widespread minor coastal impacts are likely for coastal locales along Jamaica Bay, Western Great South Bay, and Southern CT and Westchester shorelines. Elsewhere, localized minor impacts are expected.
Otherwise, high surf of 10 to 15 ft is expected on Thu along the Atlantic oceanfront, with 2 to 4 ft along the CT shoreline and out by the the points of the Twin forks. This will likely result in beach flooding and erosion, with minor damage possible to base of dune structures. Splashover onto shoreline roads and properties likely along the CT shoreline
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
NOAA New York NY Office: Watches - Warnings - Advisories
CT...Flash Flood Watch from Thursday morning through Thursday afternoon for CTZ005>012.
Wind Advisory from 9am to 6pm EST Thursday for CTZ009>012.
Coastal Flood Advisory from noon to 3pm EST Thursday for CTZ009>012. NY...Flash Flood Watch from Thursday morning through Thursday afternoon for NYZ067>075-078>081-176>179.
Wind Advisory from 9am to 6pm EST Thursday for NYZ071>075- 078>081-176>179.
Coastal Flood Advisory from noon to 3pm EST Thursday for NYZ071.
Coastal Flood Advisory from 9am to 2pm EST Thursday for NYZ178-179. NJ...Flash Flood Watch from Thursday morning through Thursday afternoon for NJZ002-004-006-103>108.
Wind Advisory from 9am to 6pm EST Thursday for NJZ006.
Small Craft Advisory until 6am EST Thursday for ANZ330-335- 338-340-345.
Gale Warning from 6am to 6pm EST Thursday for ANZ330-335-338- 340-345-350-353-355.
Small Craft Advisory until 6am EST Thursday for ANZ350-353- 355