795
FXUS61 KOKX 031129
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
729 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/...
-- Changed Discussion --
Forecast generally on track this morning. Outside of a few
showers out east, mainly dry conditions are expected this
morning.
Another hot and humid day expected for much of the region.
Any patchy low level fog and clouds expected to burn off early.
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. Max heat indices for Eastern Suffolk NY and
Southern New London CT are in the lower 90s.
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.-- End Changed Discussion --
&&
.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. The complex of showers and
thunderstorms will probably weakens as they make their way to
the eastern half of the region late this evening.
More of a lull expected late tonight into early Sunday in terms
of rain before more showers and thunderstorms are set to
develop and move within the forecast region late morning into
the afternoon 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 no 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. Cooler temperatures will keep instability
lower as well, so this will limit the strength of thunderstorms
and lead to a lower severe thunderstorm probability.
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. Monday`s forecast highs return
right back to the upper 80s to lower 90s for much of the region
with forecast dewpoints near 70. Max heat indices forecast once
again are in the mid 90s to near 100 for much of the region.
Dry conditions last through Monday but POPs trend higher Monday
night. In addition, potentially again for some areas to reach
heat advisory criteria, although this will be more based on
whether or not the max heat index reaching 100 for that
individual day as opposed to meeting the consecutive 95 to 99
degree heat index 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 /12Z SATURDAY THROUGH WEDNESDAY/... -- Changed Discussion --
Weak low pressure
will remain in the vicinity through Saturday evening with a
front stalling and lingering into Sunday.
VFR to start the day. After 20Z, another round of showers and
thunderstorms will be likely. These may be more scattered than
Friday`s line.
A SW flow is expected today between 5-10 kts at the start of the
day, then increasing to 10-15 kts with seas breezes developing
and winds becoming southerly late in the day. A few 20 kt gusts
are possible.
Winds turn light and/or variable again Saturday night from a
S/SW direction. Ceilings may lower to MVFR for eastern
terminals after 06Z Sunday, but low confidence, at this time.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No amendments expected until SHRA/TSRA develops this
afternoon/evening. Timing may be off by an hour or two.
OUTLOOK FOR 12Z 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...
Southerly flow this weekend will lead to building ocean seas
with resulting increasing trends to surf heights as well.
Breaking waves of near 3 to 4 ft this morning will reach 5 ft
this afternoon and remain near 5 ft Sunday.
Expecting increasing risk of rip currents today. There is a high
risk of rip currents at the ocean beaches forecast through this
weekend.
&&
.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.
High Risk for Rip Currents through Sunday evening for NYZ075-080-
081-178-179.
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...JM