000
FXUS61 KOKX 051445
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
945 AM EST Tue Mar 5 2024
.SYNOPSIS...
Low pressure moves through today, followed by another low pressure
system Wednesday afternoon into Thursday. High pressure then
briefly builds in during Friday ahead of another storm system
next weekend. High pressure slowly builds back in on Monday and
Tuesday.
&&
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Rain continues this mrng. The prevailing large scale pattern
continues to be driven by an active Pacific branch along with an
active pure southern branch. The southern / pineapple branch of
the jet stream will be the one that impacts our region in both
the near and short term. A mid level shortwave moves across from
the south with a light to moderate rainfall. QPF amounts will
be mainly on the order of a half to three quarters of an inch.
The first pocket of lift moves across the western half of the
area for the mid to late morning, with a secondary pocket of
lift across NW and N-NE sections later this afternoon and very
early this evening. Temperatures will average a few degrees
above normal today despite the cloud cover and onshore flow with
temperatures reaching the upper 40s and lower 50s.
The system gets further northeast late this evening as any rain
across NE sections tapers off with mostly cloudy skies remaining in
place. The lower levels will dry out with the winds shifting to the
south, then southwest. The southwest flow ushers in somewhat drier
air in the boundary layer. With a lack of separation with temps and
dew points look for perhaps some patchy fog in some spots with a wet
ground and lighter winds. Min temps will stay a good 10 degrees or
so above normal.-- End Changed Discussion --
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
For Wednesday the pacific branch lifts north of the area allowing
for the a closed mid level low to swing up from the SE state for the
afternoon and into Wed night. Much of the morning looks to be dry,
with the next slug of higher PWATs / moisture pushing up from the
south for the afternoon and evening. The HREF has many of its
members bringing pockets of moderate to locally heavy rain very late
in the day. Global guidance however has had some uncertainty with
it, especially with respect to how far west the axis of higher mean
specific humidity and PWATs ultimately gets. The ECMWF and NAEFS
Situational Awareness Tables (ESATs) have 3 to 4 standardized
anomalies with respect to the lower latitude moisture plume moving
into the area. This is based on the climatology for the time of
year, and March is not typically a favored time of year for
impactful heavy rain. The warm cloud layer and the instability is
doesn`t appear to be quite there to drive high hourly rainfall
rates, thus any potential for rainfall flooding impacts would be
driven more by duration with respect to more moderate rainfall
rates. However, antecedent conditions remains rather saturated from
previous rainfall, with antecedent conditions only worsening / more
saturated going forward in time with each subsequent rain event.
This is what is really driving the marginal to slight risk from WPC
across our area. WPC maintains the slight risk of excessive rainfall
for most of the eastern half of the area Wed afternoon through Wed
night. With respect to the global guidance, the thermal forcing
appears to be further east over the less flood prone areas,
therefore the confidence is still not quite there at the moment to
hoist flood watches. The HREF appears more bullish on this
potential, and would like to see another run before initiating flood
watches. Temperatures will run well above normal Wednesday with
mainly 50s region wide. With any heavier rainfall across eastern
sections cannot rule out a rumble of thunder or two late Wed and
Wednesday night.
The lower level jet and better mid level forcing gets further east
and north into Thursday. Look for a purely stratiform rain with the
winds having more of a northerly component. Rainfall on Thursday
will be on the lighter side, and there is the chance that rain may
completely shut off closer to mid day. Have gone with consensus PoPs
on Thursday with some likely PoPs further east earlier on, with
mainly chance PoPs for the afternoon. Temperatures will continue to
average above normal despite a good deal of clouds with mainly lower
and middle 50s.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Any leftover rain comes to an end Thursday night with drier
conditions expected on Friday and most of Friday night as high
pressure briefly noses down from the north.
A complex low pressure system will be pushing in from the south and
west this weekend with rain chances as early as late Friday night,
but rain appears to be overall more likely Saturday afternoon
through Sunday. Still a chance that thermal profiles would be cold
enough well inland for a shot at a wintry mix at times, but with
only marginally cold air to begin with and high pressure retreating
instead of trying to build in, this looks to be mostly rain even for
these areas. High pressure then follows for Monday and Tuesday with
breezy, dry and cooler conditions.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
Low pressure over the Delmarva at 14Z will move into the area
through this afternoon and gradually weaken. Then low then lifts
northeast of the area tonight.
IFR to LIFR conditions are expected through much of the TAF
period. There may be brief improvement to low end MVFR late
morning into the early afternoon. Then some of the forecast
guidance is hinting at improvement, possibly to MVFR after 06z
tonight. It is possible improving conditions hold off until
after 12z Wednesday.
Winds will be E to NE this morning, and then E to SE and lighter
this afternoon. There is a chance that winds become light and
variable late afternoon, especially at the NYC metro terminals.
Tonight, winds become more S-SE remaining around 10kt or less.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments will be likely due to variable flight change categories.
Occasional gusts possible through early afternoon.
Winds becoming lighter this afternoon.
OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY...
Wednesday: MVFR or lower. Chance of rain in the morning, becoming
likely in the afternoon into the night. E winds G15-20kt at night.
Thursday: MVFR or lower in possible rain. NE-N winds G20-25kt.
Friday: Mainly VFR. N wind gusts 15-20 kt possible.
Saturday: MVFR possible with rain. E winds G20-25kt.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Seas increase to 5 to 6 ft today as an easterly flow becomes more
southerly late in the day and evening with marginal small craft gusts
on the ocean. Seas may briefly fall just below small craft criteria
Wednesday, but this looks to be short lived as seas increase by Wed
evening. The winds increase out of the north early Thu morning with
small craft conditions more likely across all waters during the day
Thursday with 6 to 8 ft seas.
Winds and seas diminish Thursday night with conditions falling below
advisory thresholds on the non-ocean waters by Friday morning. Seas
on the ocean will however remain elevated, partly due to swell, with
5+ ft seas lingering Friday through very early Saturday morning. An
onshore flow increases Saturday afternoon ahead of the next storm
system with advisory-level conditions on all waters Saturday
night.
&&
.HYDROLOGY...
No hydrologic impacts are expected with today`s system with a
half inch to three quarters of an inch of rain.
WPC maintains a marginal to slight risk of excessive rainfall
Wednesday and Wednesday night. Rainfall totals will be on the
order of 1 to 2.5 inches, with as much as 3 inches locally
across eastern sections.
Potentially 1 to 1.50 inches of rain could fall with the following
storm system this weekend. Impacts with this event are still
somewhat uncertain as it will partly depend on the amount of rain
falling during the two rain events that will precede it.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EST Wednesday for ANZ350-353-
355.
&&
$$
SYNOPSIS...BC/JE
NEAR TERM...JMC/JE
SHORT TERM...JE
LONG TERM...BC
AVIATION...BC/MET
MARINE...BC/JE
HYDROLOGY...BC/JE