Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 241944
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
344 PM EDT Wed Apr 24 2024

.SYNOPSIS...
A cold front pushes offshore tonight. Strong high pressure builds in
later tonight through Friday and remains over the area into
Saturday and will shift to the south Saturday night as low
pressure moves northeast across the upper Great Lakes into Canada
and an associated warm front approaches. The front will lift
through on Sunday but remain nearby to the east early next week. A
cold front will approach on Tuesday, passing Wednesday morning.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Slight chance for showers this evening as a cold front pushes
offshore. Thereafter, expect clearing and a much cooler airmass to
enter the area with high pressure building in from the northwest.
Winds will slowly diminish, especially across the interior. Because
of this, temperatures will drop pretty quickly, especially thanks to
how dry the air mass will be as dew points are expected to fall into
the teens. Went on the lower side of guidance due to the abnormally
cold nature of the air mass. Freeze Watches across portions of
northeast New Jersey, Lower Hudson Valley, and inland southern CT
have been converted to Freeze Warnings as confidence is high enough,
especially given that NBM shows greater than 80% chance of seeing 32
degrees or less for lows across these areas. Frost does not look
like a concern with a large dew point/temperature spread, but is
perhaps possible in some very patchy areas.

Otherwise, dry and cold conditions for this time of year for the
rest of the forecast area, with lows dropping into the 30s to around
40.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
Dry and cool conditions continue for Thursday as the strong Canadian
high pressure continues to build in from the northwest and an upper
level trough sets up across the Northeast then pushes east later in
the day. An upper level ridge over the mid-West amplifies and slowly
heads east Thursday night through Saturday with the ridge axis
just moving over the area late in the day Saturday into Saturday
night.

As previously mentioned, cool conditions continue Thursday. Some
modification in the air mass expected for Friday, but it should
remain seasonably cool. Highs on Thursday will be in the middle
to upper 50s, then upper 50s to lower 60s for Friday.

Slightly colder temperatures are expected Thursday night as
compared to tonight with clear skies and calmer winds.
Temperatures are forecast to drop into the 20s across the
interior and Pine Barrens of Long Island. Will have to monitor
for potential of Frost Advisory/Freeze Watch for these areas
with the subsequent forecast overnight tonight and tomorrow.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Not much has changed with regards to the long-term forecast. An
omega block over the eastern CONUS will be a predominate feature
through the weekend and early next week, with its western leg over
the central states and multiple shortwaves lifting NE through the
Plains states and upper Great Lakes, its eastern leg over the
Canadian Maritimes and adjacent Atlantic, and an upper ridge over
the East.

The first of the shortwaves lifting through the Plains and
Great Lakes will send a warm front toward the area Sat night that
should then lift through on Sunday, with low chance for showers
mainly inland. A warming trend will then follow, with temps well
above normal especially from the NYC metro area north/west, with
highs well into the lower/mid 70s on Sunday and either side of 80 on
Mon. Most of Long Island and SE CT should be cooler, with highs in
the 60s, to low-70s on Mon, due to onshore flow and afternoon sea
breezes, also some intrusion of cooler maritime air from the east
depending on the position and intensity of low pressure developing
well to the east over the Atlantic.

The omega block should start to break down on Tue, with the upper
ridge weakening and a cold front approaching from the west, bringing
the chance for showers and isolated thunderstorms as moisture
increases ahead of it, particularly as it moves through early on
Wednesday. Temps on Tue should continue to be on the mild side, with
highs in the 60s across much of S CT/Long Island, and in the 70s
across the NYC metro area north/west and interior S CT.

Per NBM 50th/75th percentile forecasts, temps early next week have
potential to be a few degrees warmer than fcst, possibly upper 70s
to mid 80s on Mon, and mid 70s to lower 80s on Tue, depending on
both the strength of the ridge and onshore flow.

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
A cold front pushes offshore this evening. Strong high pressure will
then build in tonight into Thursday.

Scattered showers and an isolated thunderstorm remain possible until
around 22z. Otherwise, VFR conditions will prevail through the TAF
period.

Winds will continue to veer to the WNW-NW with the cold front
passage. Wind speeds around kt with gusts 20-25 kt likely into the
evening. A few gusts around 30 kt possible. Winds will continue
veering to the N tonight and then NE early Thursday morning. Winds
and gusts will diminish overnight with wind speeds around 10 kt or
less by day break Thursday.

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

A shower or thunderstorm remains possible through 22z.

Gusts could become occasional or end 1-3 hours earlier tonight.

OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY...

Thursday Afternoon-Friday: VFR.

Saturday: Mainly VFR. Low chance for showers with brief MVFR
conditions Saturday night.

Sunday-Monday: VFR.

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

&&

.MARINE...
The Coastal Waters Forecast with wave component details is
operational.

With building high pressure, winds and gusts gradually diminish
below advisory levels by late tonight. Ocean seas will remain
elevated into Thursday morning, and then subside below 5 feet. A
SCA remains in effect on the ocean waters until 1000 AM EDT
Thursday. With a weak pressure gradient later Thursday through
Friday night, with high pressure in control, winds and seas
will remain below advisory levels across the forecast waters.

Quiet this weekend into early next week with winds/seas below
advisory criteria. S-SW flow up to 15 kt after a warm frontal
passage could briefly push ocean seas up to 4 ft late day Sunday
into Sunday evening. Fog may also become possible Sunday night as
more humid air traverses colder waters.


&&

.FIRE WEATHER...
Relative humidity will be lowering to 30-35% early this evening
behind a cold front, with west to northwest winds gusting as
high as 25 MPH. With falling temperatures this evening relative
humidity levels will then begin to increase. With the front,
there will be little to no wetting rain. Elevated fire spread
conditions may briefly be present for NE NJ, portions of the
lower Hudson Valley, New York City, and western Long Island.

Minimum relative humidity will be in the upper teens to around
25 percent Thursday, however, winds will be under 10 MPH.

&&

.HYDROLOGY...
No hydrologic concerns through early next week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Freeze Warning from 3 AM to 9 AM EDT Thursday for CTZ005>008.
NY...Freeze Warning from 3 AM to 9 AM EDT Thursday for NYZ067>070.
NJ...Freeze Warning from 3 AM to 9 AM EDT Thursday for NJZ002-103.
MARINE...Small Craft Advisory until 10 AM EDT Thursday for ANZ350-353-
     355.

&&

$$

SYNOPSIS...JP/BR
NEAR TERM...JP
SHORT TERM...JP
LONG TERM...BR
AVIATION...DS
MARINE...JP/BR
FIRE WEATHER...
HYDROLOGY...JP/BR


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