Peconic and Gardiners Bays Marine Forecast
|This Afternoon...Se Winds 5 To 10 Kt. Waves 1 Ft Or Less. Isolated Showers And Tstms Late.|
|Tonight...Se Winds 5 To 10 Kt. Waves 1 Ft Or Less. Scattered Showers. Scattered Tstms. Patchy Fog In The Evening. Areas Of Fog After Midnight. Vsby 1 To 3 Nm.|
|Sat...Sw Winds 5 To 10 Kt. Waves 1 Ft Or Less. Areas Of Fog In The Morning With Vsby 1 To 3 Nm.|
|Sat Night...Sw Winds 5 To 10 Kt. Waves 1 Ft Or Less.|
|Sun...Sw Winds 5 To 10 Kt, Becoming S 10 To 15 Kt With Gusts Up To 20 Kt In The Afternoon. Waves 1 Ft Or Less.|
|Sun Night...Sw Winds 10 To 15 Kt. Waves Around 2 Ft In The Evening, Then 1 Ft Or Less. Chance Of Showers.|
|Mon...Nw Winds 5 To 10 Kt. Waves 1 Ft Or Less.|
|Mon Night...Ne Winds 5 To 10 Kt. Waves 1 Ft Or Less.|
|Tue...E Winds Around 10 Kt With Gusts Up To 20 Kt. Waves 1 Ft Or Less.|
|Tue Night...E Winds 5 To 10 Kt With Gusts Up To 20 Kt. Waves 1 Ft Or Less. Winds And Waves May Be Higher In And Near Tstms.|
| Area Forecast Discussion|
National Weather Service New York NY
201pm EDT Fri May 20 2022
A disturbance moves through late this afternoon and this evening ahead of a warm front which pushes through late tonight. A cold front will then approach the area from the west on Sunday, moving through Sunday night into Monday morning. Behind the front, high pressure builds in through the middle of next week. A frontal system may impact the area toward the end of next week.
Near Term - Through Tonight
Ahead of the warm front, SE flow will keep coastal locations in the 60s for temperatures with inland areas having temperatures into the 70s. Complicating factors for the high temperatures include ambient showers and extra clouds, further limiting insolation. More breaks in the clouds anticipated late this afternoon. Any extra warmth will provide more instability and with bulk and directional shear in the low to mid levels, there will be the possibility of severe thunderstorms. This is tied with an approaching shortwave aloft.
Main threat with severe thunderstorms will be damaging winds, although large hail and an isolated tornado cannot be ruled out. The factors for severe thunderstorms and tornadoes are higher to the south and west of the forecast region which include low level updraft helicity.
The timing for showers and thunderstorms is late afternoon into the early evening where the severe threat is and more in the early to late evening for Southern Connecticut and Long Island. Thunderstorms may very well become disorganized upon encountering the more maritime air this evening but models indicate warming at 850mb, which will still present enough elevated instability. This is diagnosed from Showalter indices becoming increasingly negative tonight. So that is why thunder was kept in the forecast for eastern coastal areas for even late tonight.
The CAMs have not initialized ideally and have been showing convection too far north with upstream convective activity. The MCV to the west is associated with higher instability and shear and is expected to weaken as it encounters the marine layer early this evening. The timing in the forecast is close to the timing of convection shown in the CAM reflectivity calls.
The main synoptic factor driving the forcing for convection and vertical lift is a shortwave in the mid-levels. Highest positive vorticity advection moves in late afternoon into early evening into western parts of the region and then the trough moves across the remainder of the region for this evening into start of overnight. The shortwave passes east of the region overnight with more of a trend towards negative vorticity advection across the region. POPs for showers and thunderstorms will decrease overnight from west to east across Long Island and Southern Connecticut. By start of overnight, areas to the west will already be dry. Long Island and Southern Connecticut are forecast to be totally dry by early Saturday morning with winds becoming more SW behind the warm front.
Lows tonight from the NBM 50th percentile, on the warmer side compared to the previous night, with temperatures only dropping into the upper 50s to mid 60s. There will also be fog developing especially along the coast with southeasterly winds becoming very light and with leftover ground moisture from earlier rain. The fog could become dense at times. Went with areas of fog along the coast, and patchy fog across the interior.
Short Term - Saturday Through Sunday
The first taste of summer like heat arrives for the weekend with a building mid-level ridge. Behind a departing warm front in the morning as a SW flow develops. 850 mb temps climb to around 20C with H5 heigheights approaching 590 dm. With daytime mixing, this should allow surface temps to reach the lower and middle 90s away from the coast. Along the immediate shoreline, the cool onshore / southerly wind will mitigate the heat and hold max temps down into the 80s and some 70s further east. Interior locations of CT should still manage to get into the lower and middle 90s. With subsidence aloft as the ridge axis moves overhead and offshore, abundant sunshine is anticipated on Saturday. Forecast dew points are forecast in the middle to upper 60s, which yields apparent Ts / heat indices about 5 degrees higher actual air temps. Thus heat advisories have been issued for Northeastern NJ, much of the Lower Hudson Valley, and northern portions of southern CT for Saturday. The probabilistic distribution of max temps for both Saturday and Sunday also indicate a scenario that yields max temps a degree or two warmer than the deterministic NBM. Similar conditions can be expected on Sunday as the frontal boundary should have difficulty getting further east during the day Sunday as upper level ridging tries to hold. Confidence is not as high as reaching near 100 heat indices in the same locations on Sunday compared to Saturday, thus have held off on the advisory going into Sunday, at least for now. It will still be hot and more humid than we are accustomed to, even on Sunday. With it being the first bout of heat of the season and numbers borderline in terms of the actual criteria, thought it prudent to issue the heat advisory for at least Saturday. A few daily record highs may also be broken, particularly on Saturday. See climate section below for more details.
As far as rain or convective chances for Sunday, it appears that the cold front should get delayed a bit. Thus the feeling now is that the day on Sunday should remain mostly rain / thunderstorm free. For now have introduced chance Probability of Precipitation for later in the afternoon for west of NYC and the Hudson River.
Long Term - Sunday Night Through Friday
00Z global models trending toward drier conditions behind a cold frontal passage Sunday night into Monday morning. The one exception being the operational Canadian, which significantly slows the front cold front down, not bringing it through until Monday night. The latter of which has no support from its ensemble. Thus, after a round of showers and thunderstorms Sunday evening/night, it may very will be dry through the middle of next week. For the time, have walked back rain chances Monday through Wednesday with only a slight chance of showers.
An isolated strong and/or severe thunderstorm is possible Sunday evening/night with a moderate to high CAPE environment, but weak shear.
Conditions cool and dry out behind the front, with temperatures returning to seasonable much of next week. Stayed close to the NBM for this update, though capped Probability of Precipitation at lower chance for late in the week with the approaching frontal system.
Sub-SCA (Small Craft Advisory) conditions are expected through tonight with SE winds decreasing tonight and eventually becoming SW on Saturday. Wind speeds will be well below SCA (Small Craft Advisory) thresholds. Ocean seas will be generally between 2 and 4 ft. Saturday night into Sunday gets close to SCA (Small Craft Advisory) criteria on the ocean with wind gusts getting closer to 25 kt and seas between 4 and 5 ft. Non-ocean waters though stay below SCA (Small Craft Advisory) criteria.
With warm weather expected this weekend, it is important to remember that water temps remain rather cold, in the 50s. Thus, a marine weather statement will likely be needed both Saturday and Sunday to highlight the dangers of swimming and being in waters this cold.
SCA (Small Craft Advisory) conditions are possible on the ocean waters with a cold frontal passage Sunday evening into Monday morning, when seas are expected to reach 5 ft and southwest gusts flirt with 25 kt. Otherwise, sub-SCA (Small Craft Advisory) criteria expected on all waters through late next week. Seas on the ocean zones could flirt with 5 ft Tuesday into Wednesday with E/NE flow around 15g20kt.
A short period of locally heavy downpours cannot be ruled out with thunderstorms from a mesoscale convective system this afternoon and into this evening. Overall, around a quarter to half inch rainfall amounts are anticipated on average, but with localized higher amounts possible in any enhanced convection. At this time the progressive nature of the system should allow faster storm movement and thereby limit flooding to just possible localized minor nuisance flooding with any thunderstorms this afternoon into this evening especially in poor drainage areas. No other hydrologic impacts are expected through the period.
Unseasonably warm temperatures are expected on Saturday. Here is a list of the record high temperatures for our local climate sites and their corresponding forecast high temperatures:
Central Park, NY...................93 in 1996 Forecast High: 93 JFK International Airport..........90 in 1996 Forecast High: 84 Laguardia Airport..................93 in 1996 Forecast High: 91 Islip/MacArthur Airport............90 in 1996 Forecast High: 85 Newark Liberty.....................96 in 1996 Forecast High: 95 Bridgeport, CT.....................88 in 1959 Forecast High: 83
Central Park, NY...................96 in 1941 Forecast High: 89 JFK International Airport..........94 in 2021 Forecast High: 82 Laguardia Airport..................94 in 1992 Forecast High: 88 Islip/MacArthur Airport............92 in 1992 Forecast High: 82 Newark Liberty.....................98 in 1992 Forecast High: 92 Bridgeport, CT.....................88 in 2021 Forecast High: 82
NOAA New York NY Office: Watches - Warnings - Advisories
Heat Advisory from noon to 8pm EDT Saturday for CTZ005>008. NY...
Heat Advisory from noon to 8pm EDT Saturday for NYZ067>070. NJ...
Heat Advisory from noon to 8pm EDT Saturday for NJZ002-004- 006-103>108.