112
FXUS61 KOKX 101201
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
801 AM EDT Wed Jul 10 2024
.SYNOPSIS...
A stalled frontal boundary lifts north as a warm front
today. The remnants of Beryl will approach today, and then lift
north of the area while dragging a cold front through tonight
into Thursday. The frontal boundary remains within the vicinity
of the local area Friday and into next week.
&&
.NEAR TERM /THROUGH THURSDAY/...
-- Changed Discussion --
Forecast mainly on track.
This morning some fog and low stratus may linger into the
morning for far eastern sections of the CWA, before clearing by
the afternoon as wind starts to pick up from the south due to a
passing warm front. It looks like strong capping in place
during the morning will prevent any convection from getting
started with the warm front, but this weakens later in the day.
After the warm front`s passage, the remnants of Beryl will pass to
our north and west late today into tomorrow with a cold front. This
cold front will approach late today then stall into Thursday. Being
in close proximity to the Remnants of Beryl, which comes from the
Gulf of Mexico, increased tropical moisture is expected. PWATs are
expected to rise into the 2.2-2.4" tonight which exceeds the maximum
average for our region of 2.1" per SPC`s Sounding Climatology Page.
Given the increased moisture, any showers or thunderstorms that do
occur, bring with them the risk for heavy rainfall.
As far as coverage is concerned, expecting a dry morning. In the
afternoon as the front approaches, isolated to spotty showers and
thunderstorms may pop up north and west of NYC as strong surface
heating ramps up. Not all of the latest CAMs buy into the chances,
with some popping to keep us dry through the evening, so have only
low end chance and slight chance POPs in the forecast through early
this evening. Should anything pop up, a thunderstorm would be likely
to come from it, considering the strong instability this afternoon
and early evening.
Tonight into Thursday morning, as the front approaches, a line of
showers and thunderstorms appears likely for far interior areas
north and west of NYC late tonight. This will push eastward through
the CWA into the morning on Thursday. Instability will be much lower
given the line moves through late at night and in the early morning,
but with forcing occurring along the frontal boundary and with other
sources of synoptic lift falling into place, thunderstorms remain a
possibility. And with the strongest PWATs expected tonight as the
Remnants of Beryl passes nearby, heavy rainfall could occur in any
showers or thunderstorms that do occur.
The front looks to stall over the area during the day on Thursday
and could lead to continued chances for isolated to scattered
showers and thunderstorms.
As for winds, a strong southerly 30-40 kt LLJ sets up this evening
into tomorrow morning aided by an increasing pressure gradient by
strong high pressure to our east and the passing Remnants of Beryl
to our west. Currently expecting sustained winds this evening into
Thursday morning to peak around 15-20 mph with the strongest gust
along southern coastal areas to peak around 35 mph. Winds should
remain elevated into Thursday with area gusts ranging between 20 and
30 mph, as the LLJ exits and the Remnants of Beryl passes with the
stalling front.
Temperatures will meet Heat Advisory criteria for much of the area
today. No changes have been made to the Heat Advisories since they
were last issued. Still expected heat indices to peak around 100 in
Orange county and NE NJ, with other areas still ranging between 95
and 98. Tomorrow, dewpoints are expected to lower with the front,
particularly in western areas. Temperatures may also be a degree or
two lower with increased cloud cover along the frontal boundary.
Heat Advisory criteria is not expected to be met.-- End Changed Discussion --
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
As far as Friday is concerned, not much has changed. A stalled
frontal boundary is still progged to remain over or near the western
portion of the forecast area Friday and Friday night. Surface based
lift will be limited, however mid-level lift from shortwave energy
arriving from the SW will tap into a moist atmosphere and help bring
the likelihood of showers for a good portion of the area. Additional
lift may arrive in the form of a shortwave moving clockwise around
the periphery of a western Atlantic ridge. Both areas of lift aloft
should lose influence by the end of Friday night. Shear is fairly
weak, so severe thunderstorms are not anticipated at this time.
However, scattered thunderstorms with downpours may bring some
flooding issues, since lingering tropical moisture have PWATs
remaining at anomalous values (2-2.25"). Guidance still varies
on the location of the axis of heaviest rainfall. See the
hydrology section for more details.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
Main points
* Saturday appears to be relatively speaking the coolest and
rainiest day of the long term. Forecast highs are still well into
the 80s for most locations.
* Potentially another heat wave Sunday into next week. Max heat
indices forecast get near the 90 to 100 degree range for much of
the area.
* Chances for showers and thunderstorms Monday through Wednesday
next week, mainly north and west of NYC.
* Precipitable waters potentially in the 1.5 to 1.75 range for early
to mid next week, making heavy rain a possibility with any
thunderstorms that form.
Synoptic pattern transitions from Western Atlantic ridge to more of
a zonal flow. The Western Atlantic ridge flattens out this weekend
with more zonal flow getting established Sunday and going into next
week. Next main trough moves into SE Canada towards the middle of
next week.
At the surface, a frontal boundary remains near the region this
weekend with low pressure to the south and west. This pattern does
not change too much going into the early to mid part of next week.
Airmass will transition eventually back to a hot and humid airmass
for the end of the weekend and into next week. While the forecast
area with forecast high temperatures appears to get more into the
90s, the dewpoints forecast are not quite as high as those recently
seen. Max dewpoints forecast are more in the lower 70s.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
A frontal boundary will slowly push farther north of the area
as a warm front today with a cold front approaching from the
west tonight into Wednesday.
Mainly VFR for most terminals. MVFR to IFR early this morning
then mainly VFR. Tonight, conditions go back down to MVFR to
IFR.
Otherwise, showers and thunderstorms possible this afternoon
into early evening north and west of NYC with a higher chance
late tonight for all terminals. Addressing these with prob30
groups in the TAFs, just for KEWR, KTEB, and KSWF this
afternoon and then for the all 30 hr TAF sites for overnight.
Southerly flow continues through the TAF period. Winds S near
5-10 kt heading into today will increase to near 10-15 kt.
Gusts develop as well today by the afternoon and continue
through much of the TAF period, mostly near 20-25 kt. Peak gusts
this afternoon to near 30 kt for NYC terminals and closer to 25
kt elsewhere.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of end of IFR and below conditions could be a few hours
off from TAF.
Timing of showers and thunderstorms could be a few hours off in
TAF.
OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
Thursday through Saturday: MVFR or lower possible at times with
periods of showers/thunderstorms. Otherwise VFR. SW wind gusts
near 20 kt for Thursday into Thursday evening.
Sunday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Marine dense fog advisories are in effect into early this
afternoon for the ocean, and the eastern and south shore bays of
Long Island, along with the eastern most portion of LI Sound.
Sub small craft conditions for all waters through tonight. A
southerly flow gradually increases during the day Wednesday with
small craft conditions towards the afternoon for the ocean waters
into Wednesday night. Small craft conditions will likely persist on
the ocean waters through Friday night with 5-6 ft seas and
gusts of 25 kt through Thursday. Marginal small craft
conditions are likely for the southern and eastern most near
shore waters during much of this time frame.
With a relatively weak pressure gradient in place across the
forecast waters this weekend, conditions are forecast to remain
below SCA thresholds.
&&
.HYDROLOGY...
With a very humid airmass locked in across the region and a
frontal boundary drawing closer for the mid and late week
period WPC maintains a marginal risk of excessive rainfall
northwest portions of the area today and for most of the area on
Thursday and Friday. At any point a stronger thunderstorm could
produce localized flooding impacts. Friday is expected to be
the wettest day with an average of half inch to an inch of
rainfall across the area, although locally higher totals are
possible wherever a stronger axis of rainfall sets up. Primarily
minor urban/poor drainage small stream flooding will be
possible, but there is a low threat of flash flooding.
With building humidity and higher precipitable waters moving into
place for early to mid next week, heavy rain will be a possibility
with any thunderstorms that develop. Too early to ascertain any
specific rainfall amounts, but localized heavier rainfall can be
expected.
&&
.TIDES/COASTAL FLOODING...
-- Changed Discussion --
There is a high risk of rip current development along all ocean
beaches today through Thursday. Onshore flow becomes more gusty
with building ocean seas.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...Heat Advisory until 8 PM EDT this evening for CTZ005>010.
NY...Heat Advisory until 8 PM EDT this evening for NYZ067>075-078-
176>179.
High Risk for Rip Currents through Thursday evening for NYZ075-080-
081-178-179.
NJ...Heat Advisory until 8 PM EDT this evening for NJZ002-004-006-
103>108.
MARINE...Dense Fog Advisory until noon EDT today for ANZ332-340-345.
Dense Fog Advisory until 2 PM EDT this afternoon for ANZ350-
353-355.
Small Craft Advisory from 2 PM this afternoon to 8 PM EDT
Thursday for ANZ350-353-355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JM/BR
NEAR TERM...JM/BR
SHORT TERM...BR
LONG TERM...JM
AVIATION...JM
MARINE...JM/BR
HYDROLOGY...JM/BR
TIDES/COASTAL FLOODING...