NYC Office Forecast Discussion

000
FXUS61 KOKX 230905
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
505 AM EDT Tue Apr 23 2024

.SYNOPSIS...
High pressure over the area will weaken this afternoon and
tonight as an ocean storm passes to the southeast, and as a
frontal system approaches from the west. The associated warm
front will move through Wednesday morning, followed by a
trailing cold front Wednesday afternoon. Strong high pressure
will build in the wake of the cold frontal passage from late
Wednesday into Thursday, remain over the region Thursday night
and Friday, and move offshore Friday night into Saturday. A warm
front may lift through Saturday night into Sunday, as an
associated low over the Great Lakes moves slowly eastward
through early next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Frost/freeze headlines working out mostly as expected. Temps at
08Z were below freezing in much of Orange County as expected,
also across northern New London in SE CT, with mid 30s across
most of the interior.

A mostly sunny day expected today, with few-sct high clouds
moving across from the west. As high pressure over the area
weakens and shift east, a S flow will develop and become gusty
mainly in the NYC metro area and along the coast. Temps today
along the coast may not be much different than those of
yesterday as a result, with highs 55-60, but temps inland should
be a little warmer, the 60-65 expected from interior S CT across
the Hudson Valley into NYC and NE NJ.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
Clouds should increase tonight as the frontal system approaches,
with a leading warm front bringing a chance of showers late
mainly to Orange County. S flow will continue, with lows from
the upper 30s across SE CT and ern Long Island, to the 40s most
elsewhere, to near 50 in midtown NYC.

The chance of showers will expand to cover the entire area,
first in the morning with the leading warm front, then in the
afternoon especially inland with the cold fropa. Fcst soundings
show some sfc-based instability, but do not expect thunder given
a mid level cap keeping the instability from reaching levels
colder than -10C. That said, a few showers could still produce
gusty winds to 35 mph given steep low level lapse rate and dry
sub-cloud air.

High temps on Wed will be limited to the upper 50s/lower
60s inland and out east, with mid/upper 60s for Long Island and
the NYC metro area.

Fropa Wed afternoon will be followed by a gusty W-NW flow
ushering in colder air for Wed night-Thu. Lows Wed night should
fall to the lower 40s in midtown NYC, with 30s most elsewhere
and upper 20s across the interior. Freeze conditions may once
again occur inland, all the way to the coast across SE CT, and
across the Long Island Pine Barrens, with upper 20s/lower 30s
expected. Highs on Thu should be in the lower/mid 50s, about
7-10 degrees below normal.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
An Omega blocking pattern begins to set up Thursday night and
becomes established on Friday, as a deep trough remains across
eastern Canada into the northern Atlantic, with another trough
through the Rocky Mountain region into the Plains, and a high
amplitude ridge in between. As a result systems will be slow to
move eastward into the beginning of next week. And a northern
Plains low will be slow to move into the ridge Sunday into
Monday.

With surface high pressure over the region moving offshore
Friday night, there is a lot of uncertainty with the
development and movement of a warm front Saturday night into
Sunday, as ridging remains. Regardless of the warm front, a deep
return flow sets up for late in the upcoming weekend and
temperatures initially below normal through Saturday quickly
rise to as much as 10-15 degrees above normal Saturday night
into the beginning of next week. Used the NBM guidance through
the extended period. Frost headlines may once again be needed
for the inland areas Thursday night and Friday night.

&&

.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
Weak high pressure across the region moves offshore and weakens
today. A frontal system approaches from the Great Lakes today
through tonight.

VFR.

Winds generally light and variable, to a light SW flow overnight
become southerly with winds increasing. Gusts develop late
morning, and more likely during the afternoon, less than 10 kt.
Southerly flow gradually weakens at night.

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

Gusts may be more occasional, and late in the afternoon.

OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...

Late tonight: VFR. A chance of showers late, mainly at the NYC
metro terminals, and northwest, eastern terminals toward
morning.

Wednesday: VFR, with a chance of MVFR in showers, mainly in the
morning. SW winds 10-15G15-25kt, becoming W-NW in the
afternoon, then northerly at night 5 to 10kt.

Thursday-Friday: VFR.

Saturday: Mainly VFR. Chance of showers. S winds G15-20kt.

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

&&

.MARINE...
Quiet cond to start will give way to a strengthening S flow this
afternoon and tonight. A southerly jet along the Jersey shore up
into the NY Bight and lower NY Bay will gust over 25 kt, so SCA
continues there. SCA cond should expand eastward later tonight
into Wed, with gusts up to 25 kt and seas 4-7 ft.

W-NW flow following cold fropa Wed afternoon will likely gust
to 25-30 kt on all waters from late day Wed into Wed night.
Extended SCA only for the ocean waters into this time frame for
now.

With high pressure in control Thursday night into Saturday,
moving offshore Saturday night, winds and seas across the
forecast waters should then remain below advisory levels.

&&

.FIRE WEATHER...
In tandem with PHI, issued SPS for NE NJ for elevated fire
growth potential given combo of min RH 25-30 percent, S winds
gusting to 20-25 mph, and drying fuels, for this afternoon until
around sunset. A similar combo will be in place across the rest
of the NYC metro area, much of the lower Hudson Vally, and
interior S CT along the I-84 corridor.

After a cold frontal passage Wed afternoon, cond may be even
more conducive for fire growth in the NYC metro area and NE NJ
given similar RH and W-NW winds gusting to 25-30 mph. This will
depend on whether wetting rains occur ahead of and with the
frontal passage.

&&

.HYDROLOGY...
No hydrologic concerns attm.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Frost Advisory until 8 AM EDT this morning for CTZ005>008-011-
     012.
NY...Frost Advisory until 8 AM EDT this morning for NYZ068>070-079-
     081.
     Freeze Warning until 8 AM EDT this morning for NYZ067.
NJ...Frost Advisory until 8 AM EDT this morning for NJZ002.
MARINE...Small Craft Advisory from 4 PM this afternoon to midnight EDT
     tonight for ANZ338.
     Small Craft Advisory from 5 AM Wednesday to 6 AM EDT Thursday
     for ANZ350.
     Small Craft Advisory from midnight tonight to 6 AM EDT
     Thursday for ANZ353.
     Small Craft Advisory from 6 PM this evening to 6 AM EDT
     Thursday for ANZ355.

&&

$$

SYNOPSIS...BG/MET
NEAR TERM...BG
SHORT TERM...BG
LONG TERM...MET
AVIATION...MET
MARINE...BG/MET
FIRE WEATHER...BG
HYDROLOGY...BG/MET

NWS OKX Office Area Forecast Discussion