discussion on 2023-11-08

000
FXUS61 KOKX 081446
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
946 AM EST Wed Nov 8 2023

.SYNOPSIS...
-- Changed Discussion --High pressure will briefly build across today before giving way
to low pressure tonight. The low and its associated frontal
system will pass through on Thursday. High pressure will then
begin to build in on Friday, and remain in control into early
next week.-- End Changed Discussion --

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --Forecast remains on track this morning. Cold/dry advection is
well underway as high pressure continues ridging out of southern
Canada. There will be a modest pressure gradient in place this
morning and early afternoon with potential of wind gusts 20-25
mph. These winds should diminish from west to east through mid
to late afternoon as the ridge axis builds overhead.
Temperatures will be much cooler than those of Tuesday, with
highs from the mid inland, to near 50 in some spots closer to
the coast.

The next low and its associated frontal system will quickly
approach tonight. The trend in the modeling has been to set up
the axis of strongest warm advection and middle level
frontogenesis to our north overnight. As a result, the bulk of
the precip is likely going to pass well to the north. Have
trended PoP to follow this trend, but still will carry a slight
to low chance (20-30%) PoP for the northern third of the region.
Model soundings show a very dry sub-cloud layer with the
lingering ridge axis nearby. Strengthening mid level flow will
increase overrunning enough that a few areas of light precip are
possible. However, the dry sub-cloud layer is initially going
to make it difficult for any precip to reach the surface. Wet-
bulbing should help begin to saturate this dry air, and a few
ice pellets could mix in with light rain across the northern
interior. Surface temperatures should be in the mid and upper
30s in these locations, so no impacts are expected if any ice
pellets are observed. Any ice pellets quickly transition to just
plain light rain towards day break across the interior. Closer
to the coast, it should remain mostly dry, with just a slight
chance of some light rain developing around daybreak as the
surface warm front draws closer.-- End Changed Discussion --

.SHORT TERM /THURSDAY THROUGH FRIDAY/...
-- Changed Discussion --Light rain is possible Thursday morning as overrunning continues
over the area, especially across the Lower Hudson Valley,
southern Connecticut and Long Island. The parent low pressure
shifts towards Northern New England into the afternoon. The warm
front should move into the area through the day, but likely not
lift north of the area. There is a chance that a weak secondary
low develops along the warm front, which could develop a bit
more widespread light rain late morning into the afternoon
across southeastern CT and the east end of Long Island. Have
capped PoPs off at high chance, but may need to be increased if
subsequent model cycles become more consistent on this feature.
The frontal system should push off to our east Thursday evening
with any light rain ending. Rainfall amounts remain light with
this event. PoPs over the NYC metro are just slight and
measurable rainfall may not occur.

The NBM temperature spread for highs on Thursday has become
smaller, but spread still exists mainly due to uncertainty on
placement of the warm front. Confidence is high that the warm
front will move through the southern portion of the area, but
should not fully lift north of the area. The NBM 50th percentile
seems like a good compromise with highs in the upper 50s and
lower 60s south and lower/mid 50s north. Portions of interior S
CT may struggle to reach 50 degrees. If the warm front lifts
farther north than currently expected, highs could be several
degrees warmer. If the warm front ends up staying farther south,
then highs will be several degrees cooler.

The frontal system continues pushing offshore Thursday night.
High pressure over the central states will begin building
towards the east coast into Friday. A strong jet streak will
pass to the north and will help draw in middle and upper level
moisture late Thursday night through much of Friday. The result
will be mostly cloud skies. The lower levels are very dry, but
some of the guidance continues to hint that a sprinkle or light
rain is possible near the coast. Will continue to show a slight
chance PoP for now, but the day will likely remain dry. Highs
will be close to normal in the lower to middle 50s.-- End Changed Discussion --

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
-- Changed Discussion --The extended period will be dominated by a strong and large
high pressure system that builds in this weekend and remains in
place through much of next week. A weak cold front passes
through on Saturday but a lack of moisture will prevent it from
having any sensible impact. As the high pressure builds into the
area Saturday and Sunday, a NW flow will allow colder air from
the north to filter down into the area. This will result in
temperatures being below average. Highs on Sunday and Monday
will mostly be only in the mid/upper 40s, about 10 degrees
below average.

The high should remain in place through mid next week. Some
guidance hints at a possible weak disturbance approaching from
the NW to try to break up the high on Monday but confidence is
low. Even if that were the case, limited moisture will likely
not result in anything other than some additional cloud cover.-- End Changed Discussion --

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --High pressure remains over the area today. A warm front
approaches tonight, moving through the terminals into Thursday
morning.

VFR into tonight with approach of a warm front. MVFR cigs
become increasingly likely Thursday morning from 10Z-15Z.
Earlier times likely for northernmost terminals (KSWF). Low
chance of -SHRA, possibly with sleet mixed in at KSWF, but the
probability is too low to include in TAFs.

NW flow persists around 10-15 KT. Gusts continue to diminish
this morning, with occasional gusts 20-25 KT possible into the
early afternoon where frequent gusts have ended. The flow
remains out of the NW through today and slowly decreases. Gusts
likely last longest at KISP, KBDR, and KGON. Winds lessen
tonight as they begin to shift to the NE and E overnight with
the approach of a warm front. Winds continue to veer into
Thursday morning with a S/SE wind for most coastal terminals by
12Z Thursday. Veering likely continues to SW Thursday morning.

...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

Amendments possible for end timing of gusts into morning.

Gusts may be more occasional than frequent.

OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...

Thursday: MVFR likely in the morning and early PM, then VFR. Low
chance of -SHRA.

Thursday night: Mainly VFR.

Friday: Mainly VFR. Low chance of MVFR in any -SHRA in the
afternoon.

Saturday and Sunday: VFR.

Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --

.MARINE...
-- Changed Discussion --Winds and seas have diminished below SCA criteria on all but the
ocean E of Moriches Inlet. SCA remains in effect there through
this afternoon, but it is possible that winds/seas there could
subside by early afternoon.

Sub-SCA conditions are forecast tonight with a weak pressure
gradient in place. A frontal system moves across the waters on
Thursday. The associated warm front looks to lift over the
waters, which may allow winds on the ocean to reach marginal SCA
levels. The system pushes east Thursday night. Seas may build
close to 5 ft with the passage of the system late Thursday and
Thursday night. Otherwise, sub-SCA conditions are expected into
Friday.

Sub-SCA conditions expected for the weekend and into early next
week under high pressure.-- End Changed Discussion --

.HYDROLOGY...
No hydrologic impacts are expected through early next week.

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 4 PM EST this afternoon for ANZ350.-- End Changed Discussion --

SYNOPSIS...BG/DS/MW
NEAR TERM...BG/DS
SHORT TERM...DS
LONG TERM...MW
AVIATION...MW
MARINE...BG/DS/MW
HYDROLOGY...DS/MW