000
FXUS61 KOKX 261753
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1253 PM EST Fri Jan 26 2024
.SYNOPSIS...
A frontal boundary remains south of the region through today.
A low pressure area makes its way across the region tonight.
Weak high pressure then builds in Saturday, before giving way
to another approaching low pressure area Saturday night. A
secondary low then develops offshore, deepening and tracking
south and east of the area through Monday. Weak high pressure
briefly takes hold before being stuck in between a coastal low
to the south and a Canada low to the north Wednesday into
Thursday. High pressure returns Friday.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
The frontal boundary remains just south of the area. Low
pressure to our west along the boundary will weaken today as low
pressure to our east forms and deepens. The thinking remains the
same with holding off of fog headlines for land. Current obs
and cameras show visibilities improving slightly, with some 1 to
2 mile obs remaining. The flow becoming more northerly and
daytime mixing may hinder the fog development partially.
Only lingering rain remains over eastern Long Island. Drier
conditions take place this afternoon but clouds remain with the
shortwave trough aloft still present.
Forecast highs are in the low to upper 40s, warmest across NE NJ
and coolest across the interior and eastern coastal locations.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
Another round of fog potentially for tonight, mainly this
evening. Dewpoints lower with more northerly flow late tonight
into Saturday AM, helping lower fog probabilities.
For Saturday, weak high pressure builds in. Temperatures range
similar to the previous day, low to upper 40s with dry
conditions. Temperatures forecast to be spatially in similar
pattern to the previous day as well. Northerly winds will be
light and clouds will linger with cyclonic flow aloft.
For Saturday night, the next low approaches from the south and
west. Precipitation becomes more probable, mainly in the form of
rain but for more interior locations a mix of rain and snow is
forecast.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
* Low pressure will impact the area late Saturday night into Monday.
Rain looks to be the predominant precipitation type at this time,
but could end as snow or a rain/snow mix Sunday night into Monday.
Early assessment for potential snow accumulation looks to be in
the advisory level for inland areas with little or no accumulation
at the coast. This will continue to be refined through the weekend.
* Turning colder Sunday into early next week. Forecast highs only in
the 30s for Monday and Tuesday. There is the potential for a
colder shot of air for the middle of next week, but there is a
large spread in the guidance.
Overall, the guidance is in agreement with a storm system that will
impact the area late Saturday night into Monday. There has also been
a slight warming trend in the vertical temperature profiles. That
being the case, all locations will start off rain overnight Saturday
with a potential for a changeover to snow inland Sunday night and
perhaps a snow/rain mix at the coast. Higher elevations inland could
still see this happen a bit sooner. Liquid equivalent amounts for
this event are generally around an inch, give or take a quarter
inch. Early assessment for snowfall potential is advisory level
inland and little or no accumulation at the coast. That being said,
subtle changes in storm track and magnitude will impact this
potential. The limiting factor for a big snowfall event is
marginally cold airmass and lack of a strong high to the north.
The latter of which is coming in behind the system. So dynamical
cooling will be the main mechanism to cool the column enough for
potential snow. Gusty NE winds will also accompany the system with
gust 25 to 35 mph, highest along the immediate coast. Conditions dry
out from west to east Monday, with much of the area dry by the
afternoon.
High pressure builds in for Tuesday with a clipper low dropping
southeast out of the Great Lakes and dropping west and southwest of
the area late Tuesday night into Wednesday. Solutions vary
significantly with the magnitude of the cold air to follow.
Temperatures will fall Sunday into early next week with highs in the
30s for Monday and Tuesday with lows generally in the 20s.
For the time, the NBM temperatures that were used for the midweek
period are close to normal levels, however, there is guidance that
is much colder. For example, the NBM box and whisker plots for high
temperatures Wednesday at KISP, varies from 27 to 42 with lows that
morning ranging from 18 to 36.
Energy from the clipper low, which current 00Z guidance shows
somewhere in the central to southern Appalachians Tuesday night into
Wednesday morning, will transfer energy to a developing coastal low
Wednesday night off of the Carolina shore. At the same time, a low
will be dropping down from Hudson Bay around this time with some
colder air. Some previous 12Z guidance showed 850mb temps -20C from
the polar vortex, while current guidance has significantly trimmed
back on those projections, closer to -3-6C. Goes to show the
variability between model run cycles and the uncertainty surrounding
what may transpire late in the week. For now, have gone with blended
guidance keeping temperatures closer to average. Weak high pressure
in between these systems appear to keep POPs out of the forecast or
at least very low, but given that this is near the end of the
forecast period, this may change.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
A wave of low pressure south of Cape Cod early this afternoon
will track slowly eastward through tonight. Weak high pressure
builds in behind the low for Saturday.
Ceilings will be variable this afternoon with a light NE flow,
but generally IFR, at at time MVFR, with visibilities at or
greater than 6SM as fog has dissipated. IFR ceilings are then
expected again this evening, with MVFR fog as winds become light
and variable. Then with a light northerly flow late tonight, as
drier air moves in, conditions improve to MVFR.MVFR ceilings
then remain through 18Z Saturday. There is a low chance that
improvement occur late in the forecast.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Generally expect IFR ceilings, with the potential for a brief period
of MVFR this afternoon. Conditions improve back to MVFR late
tonight as northerly winds developing. There are timing
uncertainties with changing flight categories. Moderate to low
confidence forecast into this evening.
OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
Saturday afternoon: MVFR becoming VFR by mid to late afternoon.
Saturday night: VFR early, the becoming MVFR to IFR with rain
developing after 06Z.
Sunday: MVFR or lower cond in rain. Potential for snow to mix in N
and W of the NYC terminals. NE winds G20-30kt, highest along
the coast.
Monday: MVFR or lower cond. Chance of rain and snow in the morning.
N winds G20-25kt.
Tuesday-Wednesday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
The Marine Dense Fog Advisory has been extended through early
this afternoon on the ocean waters. Fog continues to be seen on
cameras across the area along the south shore of Long Island. A
Marine Weather Statement has also been issued for the South
Shore Bays and Peconic and Gardiners Bays for patch dense fog.
Otherwise, sub-SCA conditions are forecast for all waters
through Saturday.
SCA conditions are likely Sunday into Monday, with NE gales
possible on the ocean and eastern Sound/bays Sunday night. Ocean
seas build to 5-10 ft Sunday night into Monday. Low-end gales
are possible on ocean waters Sunday night. Seas will likely
linger above 5 ft on the ocean through midweek.
&&
.HYDROLOGY...
Rain through early this afternoon will amount to less than a
half inch for most locations. No hydrologic problems expected.
Liquid equivalent totals forecast approach near an inch
Saturday night through Sunday night. Part of this will be snow.
No hydrologic problems expected once again.
In total, Thursday morning through Friday afternoon, about 0.5-1.0
inches of rainfall is expected with higher totals south and lower
totals north. There are no significant hydrologic concerns at this
time.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Dense Fog Advisory until 3 PM EST this afternoon for ANZ350-
353-355.
&&
$$
SYNOPSIS...JM/BR
NEAR TERM...JM/JT
SHORT TERM...JM
LONG TERM...BR
AVIATION...MET
MARINE...JM/BR/JT
HYDROLOGY...JM/BR