877
FXUS61 KOKX 071138
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
738 AM EDT Wed May 7 2025
.SYNOPSIS...
Weak cold front and surface trough pass today as low pressure exits
into New England. Weak high pressure takes hold tonight. A stalled
cold front with developing low pressure impacts us Thursday
afternoon into Friday. Low pressure exits northeast Friday
night into Saturday morning. A weak cold front will cross
Saturday night, with high pressure building in for early next
week.
&&
.NEAR TERM /THROUGH TONIGHT/...
Patchy areas of fog may continue into mid-morning before clearing.
A weak occluded surface low in northern New York with a mid-level
shortwave aloft will exit northeast into New England this afternoon
along with its triple point, located closer to us this morning. This
may bring a few light showers or drizzle this morning, but expected
any precip to remain isolated.
As the surface low exits this afternoon and evening into New
England, a surface trough will pass with PWATs increasing to around
1.0". This may be just enough to bring a few isolated showers to the
area later today, with the best chances in the interior, closer to
the circulation of the low.
Tonight, the low will continue to exit into the Canadian Maritimes
with high pressure briefly nosing in from the north in Canada. Light
winds could allow for another night of patchy fog.
Highs today will be in the low/mid-70s with lows in the 50s
tonight.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Key Messages:
* A stalled front and low pressure to bring prolonged period of
rainfall Thursday afternoon into Friday night.
* Periods of moderate to locally heavy rainfall possible.
* 1-2" expected with locally higher totals possible.
A cold front will set up over the area on Thursday and stall over or
nearby into Friday. At the same time, a Mid-Atlantic low will pass
along the front during this time frame. An upper-level trough will
also dig into northern New York Thursday, becoming closed and moving
nearby Thursday night into Friday. The upper-low and surface low
will then become stacked on Friday as it phases with a southern
jet stream, then exit northeast Friday night.
Low pressure along the stalled front will lead to periods of showers
Thursday afternoon into Friday, with showers tapering west to east
Friday night as the system exits. Some timing discrepancies still
exist among the 00Z guidance, with some quicker than others with the
system`s exit. Thunderstorms will be possible in the afternoon and
evening on both Thursday and Friday with marginal instability and
shear in place.
00Z guidance vary with QPF amounts. Periods of moderate to locally
heavy rainfall are possible given lift from the stalled front,
marginal instability, positive vorticity advection from the nearby
closed upper-low, some orographic enhancement of precip with
easterly flow Thursday night into early Friday, and warm air
advection at 850mb Friday afternoon and evening. PWATs should peak
around 1.25 to 1.45" which is right at or above the 90th percentile
per SPC`s Sounding Climatology Page.
Current forecasted QPF is between 1-2" Thursday afternoon through
Friday night. Its quite possible some areas could receive a few
inches more than this, depending on where the heaviest
showers/thunderstorms set up. 00Z CAMs are hinting at some
banded higher amounts late Thursday into Thursday night north
and west of NYC, particularly in the Lower Hudson Valley. As a
result, WPC has gone with a Slight Risk for Excessive Rainfall
for parts of Orange county with and Marginal Risk for the
remainder of the area on Thursday. Friday also carries a
Marginal Risk for the entire area.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
Conditions continue to improve Saturday morning as low pressure
departs to the north. While there may be a few leftover showers
Saturday morning, expect a drying trend.
Another shortwave likely crosses the area Saturday night with
associated weak cold frontal passage, with Canadian high pressure
building into its wake and gradually rising heights.
The high will keep conditions dry through Monday night. The next
chance of precip comes on Tuesday or Wednesday with the
approach of the next low pressure system.
Temperatures on Saturday will remain around seasonable levels,
however temperatures warm to above normal for the rest of the long
term.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
A trough of low pressure will be in the vicinity of the area
terminals today.
VFR today. A low chance of a shower today, but not enough
impact to include in TAFs.
SW winds 10kt or less today. Late day afternoon sea breeze
shift to S for KJFK/KLGA probable. Winds tonight eventually
shift to the W then NW late.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
no unscheduled amendments expected.
.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
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...
Sub SCA conditions likely on Thu under a weak pressure
gradient.
Next potential for SCA conditions is Friday into Friday Night,
particularly on the ocean waters, with coastal low pressure.
Conditions fall below SCA levels on Saturday and remain below SCA
levels through the start of next week.
&&
.HYDROLOGY...
Widespread moderate to locally heavy rainfall is possible Thursday
afternoon into Friday night. Total rainfall amounts will be 1-2",
but could be locally higher for areas north and west of NYC. Flood
impacts are expected to be minor for most, limited to only low-
lying, poor drainage, nuisance issues. We could see isolated flash
flood impacts late Thursday into Thursday night for parts of the far
interior north and west of NYC where banded precipitation could
set up.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...BC/BR
NEAR TERM...BR
SHORT TERM...BR
LONG TERM...BC
AVIATION...BC
MARINE...BC/BR
HYDROLOGY...BC/BR