627
FXUS61 KOKX 030835
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
435 AM EDT Sat Aug 3 2024

.SYNOPSIS...
Low pressure remains to the west along with a frontal boundary.
This frontal boundary gradually makes its way into the area
tonight into Sunday. Weak high pressure follows for Sunday night
into Monday. A cold front will slowly sag south Tuesday into
Wednesday. At the same time, a potential tropical cyclone works
northeast along the southeast coast. This could impact the
position of the front and whether or not it stalls across the
area. Refer to the latest NHC forecast information on this
potential storm.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Another hot and humid day expected for much of the region.
Any patchy low level fog and clouds expected to burn off during
the morning.

CAMs in pretty good agreement with convection holding off in
terms of development and movement into the area until mid to
late this afternoon. This allows for near peak heating and hence
temperatures warm enough with this continued very humid airmass
to make for widespread heat indices forecast in the mid 90s to
upper 90s with some locations around 100 for heat index.

Heat advisory remains in effect until 7pm for much of the area
and has been expanded to Orange NY, Putnam NY and Southern
Middlesex CT.

CAMs with mid to late afternoon convection does show some
organization of this convection. Models are indicating an
increase in 0-6 km bulk shear to 30 to locally 40 kt. PWATs are
high and expected to generally remain near 2 inches.
Thunderstorms will be capable of producing strong gusty winds
and heavy rain.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
Ongoing convection expected across much of the western half of
the forecast region during the evening, eventually getting into
more eastern areas late this evening. Instability will gradually
lower so thunderstorms probably will not be as strong but will
still present heavy rain threat.

More of a lull expected late tonight into Sunday before showers
and thunderstorms are set to develop and move within the
forecast region on Sunday. Sunday has a much earlier time window
for most convection, looking to be confined to the morning
through the first half of the afternoon for much of the region.
This will make for a relatively cooler day so not heat
advisories are expected for Sunday. However, it will remain very
humid and models are showing PWATs going slightly above 2 inches
with enhanced moisture convergence along the cold front boundary
moving into the area.

The cold front eventually moves south of Long Island Sunday
night and dissipates, with a large decrease PWATs forecast as
well. Drying conditions are expected Sunday night. However,
airmass will still be relatively warm and humid. The airmass
change will not be significant.

Dry conditions last through Monday but POPs trend higher Monday
night. In addition, temperatures forecast to increase again
Monday with potentially again for areas to reach heat advisory
criteria.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Quite a bit of uncertainty heading into next week with Tropical
Depression Four working northeast along the southeast coast. Please
refer to the latest NHC forecast on this potential storm.

A nearly zonal flow along the U.S./Canadian border begins to take a
dip across the Great Lakes and Northeast in the Tuesday into
Wednesday timeframe. This will allow a cold front to sag slowly
southeast during the time. Due to quite a bit of uncertainty in the
forecast, stayed in line with the NBM which takes the boundary
through the area Tuesday night and slowly drags through the southern
half of the CWA on Wednesday. This part of the forecast will partly
hinge on the future track of the aforementioned Tropical Depression
Four.

Model guidance still varies on the speed of the depression`s
track, which bring it over or nearby anytime from Friday to Sunday.
This discrepancy in track and timing of the tropical system across
global models may continue to fluctuate in subsequent forecasts.
Furthermore, the slowing/stalled frontal boundary may interact with
tropical moisture during the midweek time frame, leading to possible
enhanced rainfall over the region.

The best chance at this time for showers and thunderstorms will be
Tuesday late afternoon and night into Wednesday morning as the front
is forecast to settle south and east through the forecast area.
After that, plan on just having low chances for the rest of the week
with the boundary lingering close to the forecast area. This is too
far out in time to provide any more details than that, but it is
advisable to monitor subsequent forecasts, especially as we head
into next week.

A cooldown is expected for the second half of the week with the
front forecast to be south of the area.

&&

.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
Weak low pressure will remain in the vicinity through Saturday evening. MVFR to IFR, and locally LIFR in stratus, with areas of fog continue through the early morning, except VFR at KJFK, KEWR, KLGA, and KTEB. Low confidence with regard to the timing and extent of MVFR/IFR conditions early this morning. VFR after 12Z today. After 20Z, another round of showers and thunderstorms will be likely. These may be more scattered than Friday`s line. Light S to SW flow this morning, and light and variable at the outlying terminals. A SW flow is expected Saturday with seas breezes developing and winds becoming southerly. Winds turn light again Saturday night from a S/SW direction. Ceilings may lower for eastern terminals after 06Z Sunday, but low confidence, at this time. NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... VFR conditions are looking more likely for NYC terminals through the morning, but still some uncertainty with regards to the occurrence of MVFR/IFR at KJFK and KTEB. OUTLOOK FOR 09Z SUNDAY THROUGH WEDNESDAY... Sunday: Chance of MVFR or lower in afternoon/evening SHRA/TSRA. Monday: VFR. Tuesday-Wednesday: Mainly VFR. Low chance of SHRA/TSRA, with MVFR or lower. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90
-- End Changed Discussion --
&& .MARINE... Sub-SCA conditions expected for non-ocean waters through Monday night. For the ocean, southerly fetch will build seas to SCA levels this afternoon and the seas are expected to remain at SCA levels through Sunday, and potentially into early next week. In addition, this weekend during the afternoon into early evening, some 25 kt gusts are expected on the ocean. Small craft advisory starts at 2PM this afternoon and has been extended through Sunday, ending at 6PM Sunday. The middle of next week could feature building long period southerly swells from a potential tropical cyclone. Refer to latest forecast information from the NHC. && .HYDROLOGY... Rounds of showers and thunderstorms this afternoon into this evening as well as Sunday could result in minor flooding of urban and low lying areas with a low chance of flash flooding. No hydrologic issues expected Sunday night through Monday night. There is the potential for heavy rainfall Tuesday into Wednesday as a frontal boundary interacts with tropical moisture. However, it much too early for any specific details. There is also a chance that Friday through Sunday of next week could see the potential for heavy rainfall, but this will be highly dependent on the track of Tropical Depression Four, which is currently still over Cuba. Details on this will become clearer in the coming days. && .TIDES/COASTAL FLOODING... An onshore southerly flow the next two days at 10-15 kt and a building southerly swell (5-6ft) will produce a moderate rip current risk on the ocean beaches today and a high risk on Sunday. There is a chance that the risk increases to high late in the day today. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...Heat Advisory until 7 PM EDT this evening for CTZ005>010. Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for CTZ005-006-009-010. Heat Advisory from 11 AM this morning to 7 PM EDT this evening for CTZ011. NY...Heat Advisory until 7 PM EDT this evening for NYZ069>075-078- 080-176>179. Air Quality Alert from 11 AM this morning to 11 PM EDT this evening for NYZ069>075-078>081-176>179. Heat Advisory from 11 AM this morning to 7 PM EDT this evening for NYZ067-068. NJ...Heat Advisory until 7 PM EDT this evening for NJZ002-004-006- 103>108. MARINE...Small Craft Advisory from 2 PM this afternoon to 6 PM EDT Sunday for ANZ350-353-355. && $$ SYNOPSIS...JM/BR NEAR TERM...JM SHORT TERM...JM LONG TERM...BR AVIATION...BR MARINE...JM/BR HYDROLOGY...JM/BR TIDES/COASTAL FLOODING...