Area Forecast Discussion
Issued by NWS Upton, NY

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479
FXUS61 KOKX 072004
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
404 PM EDT Mon Apr 7 2025

.SYNOPSIS...
A wave of low pressure will pass to the south and east tonight,
followed by a strong cold frontal passage toward daybreak. Another
area of low pressure will then pass to the north Tuesday into
Tuesday night. High pressure builds south of the region Wednesday
into Thursday. A broad area of low pressure likely impacts the
area for the end of the week into the weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
A stationary boundary over the Mid Atlantic states and to the
southeast of the area will get kicked eastward tonight along
with a deepening frontal wave. The latter of which will produce
pockets of light rain, mainly across coastal locations into the
first half of tonight. Additional upper jet energy could even
bring another episode of light rain across far eastern LI and
SE CT during the early morning hours. Rainfall amounts will be
light and generally under a tenth of an inch. Thereafter, an
amplifying northern branch upper low/trough tracks across
across the Great Lakes tonight passing to the north on Tuesday.
The associated occluded surface low will drag a strong cold
front through the area toward daybreak. Behind the front, a
gusty WNW wind and strong CAA will drop temperatures into the
30s by daybreak, with highs on Tuesday struggling to get into
the lower and middle 40s. These readings will be about 10
degrees above normal.

Winds on Tuesday are forecast to fall just short of wind
advisory criteria. Used the NBM 90th percentile and even then
had to bump up the sustained wind and gusts a few knots. Expect
sustained wind of 20 to 30 mph to develop by late Tuesday morning
with gusts up to 40 mph. There will likely be a few higher gusts
as has been the case this winter with deeply-mixed air masses.
Winds will be slow to diminish Tuesday night.

&&

.SHORT TERM /TUESDAY NIGHT/...
Winds will gradually subside Tuesday night as low pressure
departs from the Canadian Maritimes and high pressure builds in
from the west. Lows will be well below normal with lows ranging
from the lower/mid 20s inland to the upper 20s/lower 30s at the
coast. The average date of the last spring freeze is April 1 for
the NY/NJ metro area. However, with winds staying up confidence
right now is not high enough to issue a Freeze Watch. However,
a Freeze Warning is still possible as newer guidance is analyzed
overnight. It will be very close to freezing. Again, this is
about 10 degrees below normal.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
High pres builds S of the region on Wed. Although it will be cooler
than normal with high in the 40s, it will be sunny with decreasing
winds by aftn. The full sun should offset the cold airmass, with the
NBM 5 degrees or more warmer than pure mixing from h85. This seemed
reasonable based on time of year so stuck with the output.

A weak return flow attempts to develop late Wed and Wed ngt. At the
same time, increasing mid and high clouds begin pumping into the
area from the sys currently on the Pacific coast. These will be
limiting factors for low temps Wed ngt, so frost/freeze impacts
appear unlikely attm.

BKN-OVC on Thu with the potential for some lgt rain by the end of
the day, particularly wrn zones, as lift increases.

Broad lift across the cwa with increasing theta-e Thu ngt so rain
can be expected.

Subtropical tap on Fri with a slow moving upr trof, so rain
continues Fri and Fri ngt.

As the pattern shifts ewd Sat, rain chances will shift as well. Too
soon to tell if the rain remains offshore or not, so stuck with the
blended approach and used the NBM. Pops around 50 percent as a
result.

The 12Z modeling suggests the trof may be far enough E to spare the
cwa additional rain on Sun, but confidence is not high this far out
as the overall timing of the sys could drift.

&&

.AVIATION /20Z MONDAY THROUGH SATURDAY/...
Waves of low pressure move along a stationary front south of the
area through this evening. A secondary cold front moves across the
terminals late tonight with high pressure gradually building in on
Tuesday.

Mainly IFR to MVFR through early this evening with periods of light
rain. There may be some fluctuations in flight categories at times.
The light rain should end this evening with flight categories
remaining mainly IFR until the cold front passage late tonight.
Confidence is low for the occurrence of lower visibilities tonight
(MVFR or IFR). Improvement to VFR will occur late tonight,
prevailing through Tuesday.

NE winds 5-10 kt through this afternoon. Winds will back to the N
and remain under 10 kt this evening and then shift to the W-NW late
tonight behind the cold front passage. W-NW winds quickly increase
early Tuesday, becoming 15-25 kt with gusts 30-35 kt. Peak gusts
around 40 kt possible.

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

Some fluctuations in visibilities and ceilings possible through this
evening. Low chance for visibilities to fall to IFR.

Timing of improvement to VFR late tonight may be off by 1 to 3 hours.

Timing of wind shift behind the cold front tonight may be off by 1-3
hours.

Peak gusts on Tuesday around 40 kt.

.OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...

Tuesday Afternoon-Night: VFR. NW wind gusts 25-35 kt through early
evening, diminishing overnight.

Wednesday: VFR.

Thursday: MVFR possible late with a chance of showers.

Friday: IFR possible with showers likely. E-SE wind gusts 15-20 kt
possible.

Saturday: MVFR or lower possible. Chance of showers. E-SE wind gusts
15-20 kt possible.

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

&&

.MARINE...
Gale warning have been posted for all waters on Tuesday.

Low pressure passing to the north late tonight into Tuesday
will send a strong cold front across the area with gale force
gusts of 35 to 40 kt developing mid to late morning. Gales will
likely subside in the early evening hours on the non-ocean water
Tuesday evening, but likely linger a few hours longer on the
ocean. A SCA will likely replace the gale for all waters.

Decreasing winds on Wed, but the ocean may remain at SCA lvls
due to seas for at least the first part of the day. All waters
blw SCA criteria Wed ngt into Thu. SCA cond possible, mainly on
the ocean, Thu ngt thru Sat with a slow moving low pres sys.

&&

.HYDROLOGY...
There are no hydrologic concerns through Thursday.

Several rounds of rain are likely for the end of the week into
the weekend. Only minor hydrologic impacts, if any, are expected
attm.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Gale Warning from 6 AM to 8 PM EDT Tuesday for ANZ331-332-335-
     338-340-345.
     Small Craft Advisory until 8 PM EDT this evening for ANZ350.
     Gale Warning from 6 AM to 11 PM EDT Tuesday for ANZ350-353-355.

&&

$$

SYNOPSIS...JMC/DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...JMC
AVIATION...DS
MARINE...JMC/DW
HYDROLOGY...JMC/DW