000
FXUS61 KOKX 251752
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
152 PM EDT Tue Apr 25 2023
.SYNOPSIS...
A surface trough develops across the area today and then
weakens this evening. Weak high pressure builds over the area
tonight into Wednesday morning, before giving way to an
approaching weak cold front. The front moves slowly through the
area Wednesday night into Thursday morning, followed by high
pressure building in from the west. Low pressure passes near the
region late Friday into Saturday, with another low potentially
impacting the region late this weekend into the beginning of
next week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Shower activity has expanded across coastal CT and LI along the
seabreeze.
Steep-level lapse rates from the sfc to 700 mb along with
seabreezes and a thermal trough will be the focus for spotty
shower activity and/or sprinkles through the afternoon.
A large closed low will remain centered just north of the Great
Lakes this afternoon. However, much of the lift is from the
sfc to 700 mb. With plenty of cloud cover this afternoon, highs
will be in the 50s. This is 5 to 8 degrees below normal. So,
the forecast has trended downward with this update.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
The upper closed low remains to the north of the Great Lakes
tonight, and slowly weakens, becoming an open negative trough
through Wednesday. Meanwhile surface high pressure builds over
the area tonight and moves offshore Wednesday. For tonight,
after initial clearing behind the weak low, temperatures will
drop, nearing the mid and upper 30s across the interior and the
lower 40s along the coast. Mid and upper level clouds will be
increasing late tonight as another weak low begins to approach
from the west. Temperatures may then fall more slowly late
tonight, or hold steady. With temperatures marginal, and
possible only for 2 to 3 hours, and clouds moving in, any frost
that may develop will not be widespread enough for an advisory,
so will hold off on issuing one at this time.
With near zonal flow additional upper energy quickly moves into
the area Wednesday and tracks through the area into early
Thursday. Again, any forcing is weak, and precipitable water
increasing slightly, up to 3/4 inches at times. Will carry only
chance probabilities Wednesday into Wednesday night. There is a
chance that the upper energy will be farther south, along with a
weak surface wave, and the better chances of precipitation may
end up along the coast, and south.
High pressure then begins to build toward the area for
Thursday.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
An active long term period with troughing for much of the
period and a series of disturbances moving through in the flow.
A relatively weak shortwave passes through into the start of
the weekend, bringing the chance for rain showers Friday night
and Saturday. Global guidance differs on the exact placement of
the surface low that develops, with implications on how much
rain is able to develop over the area. Much of Friday and
Saturday at the least appear overcast, with moistening
conditions in easterly flow.
Meanwhile, a more potent disturbance dives south across the
Central US. This system has the potential to be a soaker, with
ensemble means signaling several inches of liquid possible this
weekend into early next week as surface low pressure attempts to
rapidly deepen as it reaches the Eastern Seaboard and the
trough becomes negatively tilted. This would allow moderate to
heavy rain to fall much of Sunday and Monday. Given inherent
uncertainty at this stage, capped PoPs at 70% and winds at 30 kt
for this update.
Persistent onshore flow and wet weather will keep temperatures
through the period near or slightly below normals for the time
of year. Other than previously noted, national blended guidance
was followed with subtle adjustments.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
A trough moves through this afternoon with high pressure
building in behind it. Generally VFR, low chance of brief MVFR
or lower in any -SHRA that may move through.
SW winds shift to the W then N and NE overnight at 10 kt or
less. Wind at all terminals may become light and variable
overnight. Winds turn S or SE on Wednesday with the high
shifting offshore, speeds remain 10 kt or less.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Brief MVFR or lower conditions possible in any -SHRA that move
through terminals through 00Z Wednesday.
OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY...
Wednesday: VFR. A chance of rain showers in the afternoon into
the night with MVFR possible.
Thursday: VFR. Possible rain showers and MVFR, mainly east of NYC
terminals during the day.
Friday: Mainly VFR. E wind gusts 15-20 kt.
Friday Night-Saturday: Increasing chances of rain showers.
Possible MVFR or lower at times. E wind gusts 20-25 kt.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Winds and seas remain below small craft advisory levels
through Thursday as high pressure builds toward the waters
through tonight. A weak front then moves through the waters
Wednesday night into early Thursday.
Low pressure passing near the waters late Friday into Saturday
will lead to increasing easterly flow. Wind gusts of 25-30 kt
are possible on all waters and ocean seas build to 5 ft during
this time.
Another area of low pressure may impact the waters late this
weekend, bringing the chance for widespread SCA conds, with
gales possible for a period as well.
&&
.HYDROLOGY...
Deepening low pressure may impact the region late this weekend,
bringing the potential for several inches of rainfall across
the region. Hydrological impacts are possible during this time
period.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...DR/MET
NEAR TERM...MET/DW
SHORT TERM...MET
LONG TERM...DR
AVIATION...JP
MARINE...DR/MET
HYDROLOGY...DR/MET