577
FXUS61 KOKX 061754
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
154 PM EDT Tue May 6 2025
.SYNOPSIS...
A frontal boundary remains near the region today as high pressure
moves across the Canadian Maritimes. At the same time, a broad area
of low pressure over the Ohio Valley will slowly track east. The
front gradually north tonight, while low pressure approaches from
the west. The low will then slide northeast through the area on
Wednesday. A cold front will approach from the northwest on Thursday
and stall nearby Thursday night as low pressure develops along it
over the Mid Atlantic region. Low pressure will track over or just
southeast of the region Friday into early Saturday, before heading
up the New England coast. Another cold front will approach from the
northwest on Sunday.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Updated forecast to lower POPs over western portions of the
forecast area, including NYC, northeast NJ, and Lower Hudson
Valley for the next couple of hours at least as the line of
showers that was stretching from the Great Lakes region to off
the Mid-Atlantic coast earlier has pushed east, along the slowly
moving cold front. Showers and thunderstorms are expected to
develop in the aforementioned areas later this afternoon into
the early evening hours as the upper low and associated cold
pool aloft slowly moves northeast.
While the forecast calls for mostly cloudy skies, there is a
chance that some partial clearing occurs. If it does, there may
be a bit more instability this afternoon, especially west of the
NYC metro area. There still looks to be enough of a marine
influence to keep it more elevated and unlikely to reach severe
limits. With the upper low approaching, impulses will move in
from the south with additional bands/pockets of rain. Localized
amounts up to an inch will be possibly with potential training
of cells in a deep-layered southerly flow. Minor nuisance
flooding will continue to be possible.
Temperatures will climb into the middle and upper 60s to lower
70s.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
The threat of showers and possible thunder continues tonight with
the best chances for any storms west of NYC, mainly early in the
period where the airmass has its best chance to be unstable. POPs
gradually decrease after midnight, but don`t completely go
away.
As the low lifts north of the region, the trough axis moves over the
area. As the trough moves across the area and interacts with a cold
pool aloft plus any daytime heating should result in enough
instability for at least some showers and thunderstorms from about
late Wed morning into the evening. The best chances for any storms
right now appear to be N and NW of NYC.
Lows tonight fall into the 50s. Daytime highs on Wednesday will be
in the 60s and lower 70s.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
No significant changes in the overall forecast pattern through the
long term and stuck fairly close to the previous forecast/NBM.
The period starts off Wednesday night with low pressure departing
the region with drier conditions working into the area. The drying
conditions in the wake of this low will be short lived as the next
cold front approaches Thursday afternoon and evening.
Good agreement in surface cyclogenesis over the Mid Atlantic region
along the cold front Thursday night into Friday as the digging
northern stream trough phases with the southern jet and closes off
at its base across the Central Appalachians. One change from the
previous forecast is the timing, with the latest NBM speeding up the
timing of this system. Regardless, Friday appears to be a rather wet
day, the question is how quickly does this system depart the region.
Will it be Friday later afternoon/evening or does is slow down
enough that the does not depart until late Friday night into early
Saturday.
Either way, expect a period of moderate to locally heavy rain late
Thursday night into Friday with deep layered lift and convergence of
Gulf/sub-tropical moisture feed over the region as low pressure
tracks over or near the region.
Conditions improve on Saturday in wake of the low pressure system.
Another shortwave likely crosses the area with cold frontal passage
Sunday afternoon/evening. Expect dry conditions to start the week as
high pressure builds back into the area for Monday and Tuesday.
Temperatures will be near to slightly above seasonable for Thursday,
falling to a few to several degrees below seasonable Friday with low
pressure affecting the area. Temperatures then moderate back to
normal on Saturday, then above seasonable for Sunday into early next
week.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
Frontal boundary lingers nearby through this evening, exiting
north and east into Wednesday.
Mainly IFR or lower with stratus, areas of mist and fog, and
periods of rain thru this afternoon. Quick improvement to MVFR
then VFR early evening, toward and after 00Z. Showers
anticipated to become much more isolated during this time as
well. Outside chance IFR conds could redevelop in spots and fog
potentially lingers for eastern terminals, mainly KGON, past 6Z
Wed. Thunder continues to be omitted from TAFs, but can`t be
entirely ruled out this afternoon. A few spotty showers possible
on Wed, but coverage and chances too low to include in TAF at
this time.
SE flow this afternoon, speeds around 10 kt. A few gusts toward
20 kt could develop, but expected to largely remain more
occasional. Flow lightens and goes southerly tonight, then WSW
or SW on Wed with speeds once again near 10 kt.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Conditions may fluctuate between LIFR and VFR at times but
largely remain IFR or LIFR thru the day.
Isolated thunderstorm cannot be ruled out into late day.
Timing of improvement could be off by a couple of hours.
.OUTLOOK FOR 18Z WEDNESDAY THROUGH SATURDAY...
Wednesday: Possible IFR/MVFR early, then mainly VFR. Chance of
showers and slight chance of thunderstorms.
Thursday: MVFR possible with a chance of showers, mainly at
night.
Friday: MVFR or lower possible with a chance of showers. A
slight chance of thunderstorms.
Saturday: Mainly VFR, except MVFR or lower possible in slight
chance of showers.
Sunday: VFR.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Marginal SCA conditions for seas around 5 ft will continue through
the day Tuesday in an E/SE flow. Latest NWPS guidance has the 5 ft
seas continuing into tonight, so will extend the SCA to cover that
time period. With uncertainty with just how long the 5ft seas last,
will extend all the ocean zones through tonight, however as seas
fall, the SCA may be able to end early.
Marginal 4-5 ft ocean seas possible Wed into Wed night in mainly a
residual E/SE swell, with sub SCA conditions likely on Thu under a
weak pressure gradient.
Next potential for SCA conditions Fri/Sat on all waters with coastal
low pressure. Low prob for gales on the ocean in E/SE flow ahead of
the low if stronger coastal development evolves.
&&
.HYDROLOGY...
An additional 0.5-1.50 inches of rainfall will be possible with
locally higher amounts possible in any thunderstorms or storm
training through tonight. Generally looking at nuisance ponding
of water with just an isolated flash flood threat.
There is the potential for a period of moderate to locally
heavy rain for late Thursday night and Friday time period.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EDT Wednesday for ANZ350-353-
355.
&&
$$
SYNOPSIS...BC
NEAR TERM...BC/JP
SHORT TERM...BC
LONG TERM...BC
AVIATION...DR
MARINE...BC
HYDROLOGY...BC