Long Island Sound West of New Haven CT / Port Jefferson NY Marine Forecast
|Today...S Winds 5 To 10 Kt. Seas 1 Ft Or Less. Chance Of Showers And Tstms This Afternoon.|
|Tonight...Sw Winds 5 To 10 Kt. Seas 1 Ft Or Less.|
|Thu...S Winds 5 To 10 Kt. Seas 1 Ft Or Less.|
|Thu Night...Se Winds Around 5 Kt. Seas 1 Ft Or Less.|
|Fri...E Winds 5 To 10 Kt. Seas 1 Ft Or Less. Chance Of Showers In The Morning, Then Showers Likely With Chance Of Tstms In The Afternoon With Vsby 1 To 3 Nm.|
|Fri Night...E Winds 10 To 15 Kt, Diminishing To 5 To 10 Kt After Midnight. Seas Around 2 Ft In The Evening, Then 1 Ft Or Less. Chance Of Tstms. Showers. Vsby 1 To 3 Nm.|
|Sat...Ne Winds Around 5 Kt, Becoming Nw In The Afternoon. Seas 1 Ft Or Less. Showers And Tstms Likely. Vsby 1 To 3 Nm.|
|Sat Night...W Winds Around 5 Kt. Seas 1 Ft Or Less. Chance Of Showers And Tstms In The Evening. Patchy Fog After Midnight. Vsby 1 To 3 Nm.|
|Sun...Sw Winds 5 To 10 Kt. Seas 1 Ft Or Less. Chance Of Showers And Tstms In The Afternoon.|
|Sun Night...Sw Winds 5 To 10 Kt. Seas 1 Ft Or Less. Chance Of Showers And Tstms In The Evening. Winds And Seas Higher In And Near Tstms.|
Area Forecast Discussion|
National Weather Service New York NY
605am EDT Wednesday July 8 2020
A weak warm front will lift to the north by daybreak. An inland surface trough will then linger this afternoon, followed by weak high pressure through Thursday. Low pressure will then approach from the south Friday into Saturday, followed by a series of weak fronts moving through from later Saturday into early next week.
Near Term - Until 6pm This Evening
Low clouds over the area especially inland should gradually erode this morning with daytime heating. This heating will also increase instability going into this afternoon, with MLCAPE as high as 1500 J/kg per NAM. Per CAM's expectation is that convection will initiate early this afternoon north of the CWA over the Catskills and mid Hudson Valley in the vicinity of the surface trough and as mid level shortwave forcing moves across, with activity drifting down into the area this afternoon. Have likely/categorical Probability of Precipitation for tstms inland NW of NYC, with chance PoP for the metro area and southern CT. Shear is weak so not expecting organized convection, but WINDEX values of 50-60 kt and isolated DCAPE values close to 1000 J/kg are suggestive of the strongest cells capable of strong winds.
High temps today should be a little above guidance, with lower 90s expected in urban NE NJ, and mid/upper 80s elsewhere. This plus dewpoints in the upper 60s should yield heat index values in the mid and upper 90s for urban NE NJ both today and Thu, hence a heat advy has been issued there for this afternoon through Thu afternoon.
Low temps tonight will range from the mid 60s to lower 70s.
A moderate rip current risk is expected today due to relatively long period SE-S swell of 3 ft and S flow 10-15 kt.
Short Term - 6pm This Evening Through 6pm Thursday
Convection should wane late today as as shortwave forcing aloft pushes east, allowing ridging to build in aloft for Wednesday night. This upper ridging and associated subsidence will lead to a hot day for NYC and the interior, with high temps in the lower 90s, and heat index values in the mid and upper 90s except for Long Island and coastal SE CT, where HI values should peak in the lower 90s.
There is the potential for some isolated to widely sct showers/tstms well inland in an unstable, but capped and weakly sheared environment.
There is a moderate risk for rip current development at Atlantic Ocean beaches on Thursday as long period southerly swell continues.
Long Term - Thursday Night Through Tuesday
Low pressure will move up the Mid Atlantic coast on Friday, passing over the region Friday night into Saturday morning. Showers and thunderstorms are expected, especially Friday afternoon and evening likely just north and east of the surface low as it taps into a warm conveyor belt of Gulf and subtropical Atlantic moisture. Still low confidence on location of this heavy rain potential, as well as potential for breezy conditions on the east side of the low, as a potential 30-40 kt LLJ develops.
An upper-level trough and its associated cold front will move into the area Saturday, resulting in hot and humid conditions and the increase chance for showers and thunderstorms on Saturday and Sunday. The cold front will move off to the east Monday, but the upper-level trough will remain overhead bringing a potential for diurnal convection as well as a gradual trend to a more seasonable airmass through early next week.
Sub-SCA (Small Craft Advisory) conditions are expected on all waters through Thu night. As low pressure approaches from the south, SCA (Small Craft Advisory) conds expected mainly on the ocean from Fri into Sat, with peak wind gusts 30 kt and ocean seas as high has 6-8 ft.
A localized urban and poor drainage flood threat exists with any thunderstorm activity through Thursday.
There is increasing potential for more widespread heavy rain Friday into Saturday as low pressure moves up the coast. Rainfall of at least 1-2 inches is likely, with potential for 2-4+ inches in heavier bands just east of where the surface low tracks, which is still uncertain, and could take place anywhere from NYC out to southern New England.
NYC NOAA Weather Radio Station KWO35 (162.55 MHz) is undergoing its final stages of testing, and is operating at full power.
NOAA New York NY Office: Watches - Warnings - Advisories
CT...None. NY...None. NJ...Heat Advisory from noon today to 6pm EDT Thursday for NJZ004- 006-103>108. MARINE...None.