382
FXUS61 KOKX 151445
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
945 AM EST Wed Jan 15 2025
.SYNOPSIS...
High pressure gradually builds in from the west through tonight,
then gives way to a weakening frontal system that approaches
from the west on Thursday. High pressure will then briefly
follow for Friday. A cold front moves through this weekend with
a series of frontal waves passing near or south and east of the
area through early next week. Strong high pressure then brings a
frigid airmass through the middle of next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
Deepening low pressure east of the Canadian Maritimes will move
farther out into the North Atlantic through tonight, while high
pressure centered over the Ohio Valley works slowly east. As
the pressure gradient begins to weaken later today into tonight
winds will begin to weaken. Before then though, plan on NW gusts
today of 25 to 30 mph. The airmass will be colder with highs
ranging form the upper 20s inland, to the lower 30s along the
coast. This is about 5 to 8 degrees below normal. For tonight,
with gradually diminishing winds, lows will bottom out in the
mid to upper teens for most locations, except the lower 20s for
the NYC metro.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
The surface ridge axis moves into the area toward daybreak
Thursday and then east with a developing light southwest flow.
An amplifying shortwave trough digging SE from the Great Lakes
on Thursday will result in increasing clouds mainly in the
afternoon. The associated frontal system dissipates as it
approaches the area, however, there should be some lift with the
upper trough as it works across the area during the afternoon
and nighttime hours. NBM PoPs are negligible for most of area
with the exception of far eastern LI. However, this consensus
approach with upper level disturbances in the NW flow has at
times been deficient this season. Nam3km and HRRR simulated
reflectivity also show increasing returns from late afternoon
into the evening overspreading the area. Thus, have introduced
20 to 30 PoPs for snow shower activity Thursday afternoon and
night. The precipitation looks to be light with possibly a
couple of hundredths of an inch liquid equivalent. One area to
watch though is far eastern LI where weak low pressure develops
to the southeast. This could increase the liquid equivalent
some with perhaps a light coating of snowfall. However,
confidence is low at this time. Highs Thursday will be in the
upper 20s to lower 30s with nighttime lows in the teens inland
and 20s at the coast.
The upper trough passes to the east early Friday with shortwave
ridging moving in ahead of another amplifying trough moving
into central Canada and the upper Midwest. This will become a
player in the weather over the weekend. At the surface, high
pressure will work across the area. Temperatures will warm some
with highs in the upper 30s to around 40 with plenty of sunshine.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Surface high pressure south of the area on Friday night and a large
low pressure north of the Great Lakes region in Canada will allow
for increased southerly flow for the area. This will increase
moisture and temperatures ahead of an approaching cold front from
the parent low moving well north of the area on Saturday. Increased
temperatures into the upper 30s and low 40s will allow for mainly
rain to fall over the area on Saturday with the cold frontal
passage. A frontal wave looks to develop along the cold front to the
south of the area and pass to the south and east, largely missing
the area as it passes by Saturday night into Sunday.
In the wake of the departing cold front, mid-level energy continues
to approach the area from the southwest and develops a weak low
pressure system over the Southeast US and Mid-Atlantic. There is
some uncertainty as to how quickly and where the low develops and
eventually tracks which will determine out p-type and the amount of
precipitation the area receives. The ECMWF and CMC are more on board
with a closer low pressure system passing to the south bringing a
period of light rain/snow or mix of both to the area, where the GFS
has a more suppressed and slower system that more closely follows
the departing cold front offshore through early Monday.
Beyond Monday, much of the week looks dry and cold as an arctic high
pressure system settles over much of the Central US. The area will
remain in between a large low pressure system well to the northeast
and the approaching high pressure so a brisk and persistent NW flow
will allow for dry and frigid air to move into the area for the
middle of the week. High temperatures on Tuesday may not rise out of
the low 20s for much of the area with cold temperatures remaining
for Wednesday with highs in the mid-20s.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
The area terminals remain in between low pressure to the
northeast and high pressure to the southwest through the TAF
period.
Gusty WNW-NW winds and VFR conditions expected through the TAF
period. Winds will be generally direction 290-310 today with
sustained wind speeds of near 15-20 kt and gusts near 25-30 kt.
Some gusts may reach 35kt. The strongest winds will be from late
this morning into this afternoon. Gusts subside tonight and
wind backs to more W/WSW Thursday morning.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Peak gusts 3-5 kts higher than gusts in TAF are possible during the
TAF period.
Timing of when gusts end in the TAF could be 1-3 hours off.
.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
Thursday: Mainly VFR. Light snow showers possible in the
afternoon and at night with MVFR or lower possible.
Friday: Mainly VFR.
Saturday: MVFR or lower at times with rain likely, possible snow at
night. SW wind gusts 15-20 kt during the day.
Sunday: Chance for MVFR or lower at times with possible rain/snow.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
A gusty NW flow of 20 to 30 kt will continue on all waters through
the day, but diminish toward evening. Sub-SCA conditions are
forecast to develop across the non-ocean waters by early this
evening, and by early morning on the ocean. Expect sub-SCA
conditions as a frontal system dissipates to the west on
Thursday and high pressure builds over the area on Friday.
SCA conditions likely develop on the ocean with gusts of 25kt and
waves near 5 feet ahead of a cold frontal system for a brief period
on Saturday before falling back down below SCA conditions Saturday
night. Waves develop once again Sunday afternoon with increased NW
flow allowing for SCA conditions into at least early Monday.
&&
.HYDROLOGY...
No significant hydrologic impacts are expected into early next
week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EST this evening for ANZ331-
332-335-338-340-345.
Small Craft Advisory until 1 AM EST Thursday for ANZ350-353-
355.
&&
$$
SYNOPSIS...DW/MW
NEAR TERM...MET/DW
SHORT TERM...DW
LONG TERM...MW
AVIATION...JM/MW
MARINE...DW/MW
HYDROLOGY...DW/MW