000
FXUS61 KOKX 261821
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
221 PM EDT Mon Jun 26 2023
.SYNOPSIS...
A pre-frontal trough approaches today and will move across the
area this evening into tonight. A slow moving frontal system
will then impact the area Tuesday into the late week. Weak high
pressure tries to move in Friday before another frontal system
approaches from the west impacting the region through the
weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
The fcst has been updated thru tngt.
Shwrs and tstms continue to track newd from the lower Hudson
Valley to nrn NJ. This activity non-severe attm with activity
elevated earlier, and a present lack of significant instability.
As some clearing occurs this aftn, at least 2000 J/kg of SBCAPE
should develop mainly west of the Hudson River. LAPS already had
1500 just s and w of the cwa at 16Z. As CIN continues to go to
zero, additional tstms should blossom over across NJ thru the
late aftn/early eve. The Hudson Valley should be an hour or so
behind regarding initiation.
Tstms track newd per modeled storm motion, encroaching on more
stable coastal areas including NYC. Challenge will be how
strong and far storms are able to maintain into this more stable
airmass.
Pops for this aftn and eve have been reduced to slight chance
for most of LI into ern CT, with mainly chance/sct pops
elsewhere thru the period. Likely probs for the Hudson Valley
thru NJ.
The main svr threat will be large hail and damaging winds. Wind
threat will be higher than earlier today with greater
instability and convection rooted in the BL.
After convection this aftn/eve, the focus becomes the upr low
over Lake Huron and the associated wave coming off Lake Erie.
Went close to the NAM for pops with this to try to get some
decent timing. There is still room for adjustment as the
activity evolves, but it essentially looks like a round of shwrs
and tstms traversing the cwa overnight.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
The region may lie in a relative min in any convection Tuesday
morning. The guidance has continued to signal the initial area
of instability and lift east of the area in the morning.
However, there could be subtle shortwaves in the flow that may
bring a shower or storm ahead of potentially more organized
convection Tuesday afternoon and evening as the vertically
stacked low and frontal boundary approach. Instability should
increase, especially from the NYC metro on north and west. This
will likely bring another round of showers and thunderstorms.
There is still some uncertainty in the convective environment
and how much the atmosphere is able to recover from Monday. SPC
has the eastern half of the area in a marginal risk in its
latest Day 2 outlook. Locally heavy rainfall is possible with
localized flash flooding potential across NE NJ and the Lower
Hudson Valley. Have adjusted PoPs to better reflect the latest
model trends. Precip probabilities are generally in the chance
category in the morning and then increase to likely east and
categorical north and west late in the afternoon and evening.
Showers and few storms are possible the first half of Tuesday
night, but lowering instability should help diminish coverage
heading into Wednesday morning.
It will remain muggy Tuesday with highs in the upper 70s to
around 80 degrees.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
The upper trough axis will remain to our west on Wednesday with
the surface boundary in the vicinity. These features all
support increasing chances for showers and thunderstorms,
especially in the afternoon and evening.
It will remain muggy Wednesday, but high temperatures will
likely stay below average for this time of year in the upper 70s
to around 80 degrees.
The upper trough and closed low will only slowly move overhead
into Thursday. Shower and scattered t-storm activity remains
possible, especially in the afternoon and evening. The trough
and associated frontal system may start to shift to the east on
Friday with weak high pressure trying to settle, but confidence
how this evolves is still quite low. 700mb RH values from
deterministic models would suggest some moments of sun in
between periods of clouds on Friday.
Look for daily max temps to average below normal with a good
deal of daytime cloud cover anticipated on average throughout
the period. There may be a day towards Fri or Sat where daytime
temps may get closer to normal. Night minimums should average
close to normal with higher humidity due to a persistent
southerly flow and a good chance of night time cloud cover.
Mainly used NBM for temperatures.
Late Saturday into Sunday another frontal system will approach
us from the west increasing southerly flow and thereby
increasing available moisture and keeping temperatures warm.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
-- Changed Discussion --
A warm front will remain nearby, nearly stationary through the
TAF period.
VFR conditions outside of any showers and thunderstorms this
afternoon. MVFR or lower as fog and low stratus affects the
forecast area once again tonight. Best chances for MVFR is after
00Z-01Z, then IFR or lower is possible after 03Z. These
conditions will occur a few hours earlier for terminals along
the coast.
Outside of thunderstorms, winds will be around 10 kt during the
day today out of the S to SE, weakening to under 10 kt tonight.
Slightly stronger winds of 10 to 15 kt by mid Tuesday morning.
A line of showers and thunderstorms currently pushing northeast
of the metro terminals will move through the Lower Hudson
Valley through around 20Z. Another area of showers and
thunderstorms is currently developing to the southwest over
western central and New Jersey and eastern Pennsylvania will
also head northeast this afternoon. This area of showers and
thunderstorms looks like it could lift north of and bypass the
metro terminals, but will likely affect KSWF. However, will
have to monitor those storms and their development and if the
path or coverage of the storms change, then will include TEMPO
for TSRA. They could could affect KEWR around 20Z. Thereafter,
the best chances for showers looks to be after 00Z, but there is
uncertainty as to how much thunder will occur with these
storms. Better chances for thunder come Tuesday morning into the
afternoon.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments likely due to uncertainty in thunderstorms coverage.
OUTLOOK FOR 18Z TUESDAY THROUGH FRIDAY...
Tuesday afternoon and Wednesday: Showers. Tstms with gusty
winds and hail possible, especially afternoon/evening. MVFR cond
expected, IFR possible.
Thursday: Chance of showers and a slight chance of tstms. MVFR or
lower possible at times.
Friday: Becoming VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
The dense fog advisory has been allowed to expire. Some fog may
also persist out east through the afternoon which has occurred
the last few afternoons.
Otherwise, both winds and seas are expected to remain below SCA
criteria through the day before increasing southerly flow helps
build seas to around 5 ft tonight. Winds may also come close to
25 kt on the ocean, especially on Tuesday with seas 5 to 7 ft.
Seas are expected to remain elevated into Wednesday night
decreasing during the day on Thursday. Conditions then largely
remain below SCA through the rest of the period, with the
possibility of 5 ft waves over the ocean waters Friday night.
&&
.HYDROLOGY...
There is a continued risk of minor flooding and localized flash
flooding, mainly late this afternoon into this tonight in
showers and thunderstorms. WPC has a marginal risk of excessive
rainfall across much of the area with a slight risk across
interior NE NJ and interior Lower Hudson Valley.
A localized risk of flash flooding continues on Tuesday, mainly
across NE NJ and the lower Hudson Valley. However, locally heavy
rainfall is possible in any showers or thunderstorms which could
produce minor flooding.
Hydrologic impacts are also possible Wednesday into Thursday,
but may be dependent on where the heaviest rainfall occurs
through Tuesday. WPC currently has a marginal risk of excessive
rainfall N of the region both Wednesday and Thursday.
&&
.TIDES/COASTAL FLOODING...
The moderate risk of rip current development continues for all ocean
beaches today. The risk is high on Tuesday due to stronger
southerly flow and higher seas.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 6 PM this evening to 6 PM EDT
Tuesday for ANZ350-353-355.
&&
$$
SYNOPSIS...DS/JT
NEAR TERM...JMC
SHORT TERM...DS
LONG TERM...JT
AVIATION...JP
MARINE...DS/JT
HYDROLOGY...DS/JT
TIDES/COASTAL FLOODING...