000
FXUS61 KOKX 261148
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
648 AM EST Fri Jan 26 2024
.SYNOPSIS...
A frontal boundary remains south of the region through today as
low pressure travels along it. Another low pressure area makes
its way across the local region tonight. For Saturday, both the
low pressure areas and frontal boundary will be moving well east
of the area. Weak high pressure then builds into the local
region 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/...
-- Changed Discussion --
Multiple runs of the HRRR depict dense fog moving northward and
developing within the area this morning. Hoisted marine dense
fog advisory until 18Z for the ocean waters where visibilities
will likely become less than 1 mile. Not confident enough to
issue dense fog advisory for anyplace else yet with
visibilities still appearing to be relatively good.
Otherwise, some minor adjustments made to better match with
observed trends. Periodic rain continues this morning and
becomes more intermittent by early this afternoon.
Rain into this morning, tapers off from west to east later this
morning into start of this afternoon.
Fog is forecast this morning. This could be potentially dense
along the coast. HRRR indicates this but does not maintain a
large area for more than a few hours.
The flow becoming more northerly and daytime mixing may hinder
the fog development partially.
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.-- End Changed Discussion --
&&
.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 /12Z FRIDAY THROUGH TUESDAY/...
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A frontal boundary remains in the vicinity this morning as a wave of
low pressure tracks northward, with another wave developing off the
Delmarva tracking east during the day Friday.
IFR and occasional MVFR conditions prevail over the morning
next few hours, with pockets of LIFR possible towards mid-
morning. IFR conditions should prevail for much of Friday, with
pockets of LIFR for some terminals. Brief improvement to MVFR
for the afternoon, before IFR returns towards Friday evening,
with pockets of LIFR possible once again in any areas of fog.
The winds will be ENE this morning and around 10-12 kt for city and
coastal terminals into the morning push. The winds will then become
more NE and N on Friday with any light rain and drizzle ending for
the afternoon. The winds lighten into the afternoon and evening
push.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Conditions will vary from IFR to LIFR at times throughout the TAF
period, with low confidence in the timing of flight category
changes. Improvement to MVFR conditions for Friday afternoon is low
confidence.
OUTLOOK FOR 12Z SATURDAY THROUGH TUESDAY...
Friday night: IFR or lower cond are possible in areas of fog.
Saturday: Early morning IFR or lower becoming VFR by mid to late
morning.
Saturday night: Rain developing with MVFR to IFR cond.
Sunday: MVFR or lower cond in rain. Potential for snow to mix in N
and W of the NYC terminals, with IFR possible by early evening. NE
winds G20-30kt.
Monday: MVFR or lower cond. Chance of rain and snow in the morning.
N winds G20-25kt.
Tuesday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
-- Changed Discussion --
As mentioned in near term section, marine dense fog advisory in
effect until 18Z today for the ocean zones.
SCA for the ocean goes until 12pm EST today. This was extended
for western ocean zone after noting a recent increase in wave
height at Buoy 44065 to near 5 ft. New Wavewatch guidance
verifies a little better with this observation compared to SWAN
so manually adjusted wave heights a little higher for this
morning. There will also be some easterly gusts to near 25 kt on
the ocean but more for the first half of this morning.
Otherwise, for non-ocean waters are below SCA criteria. For this
afternoon through Saturday night, sub-SCA conditions are
forecast for all waters.
SCA conditions are also 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.-- End Changed Discussion --
&&
.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...
-- Changed Discussion --
CT...None.
NY...None.
NJ...None.
MARINE...Dense Fog Advisory until 1 PM EST this afternoon for ANZ350-
353-355.
Small Craft Advisory until noon EST today for ANZ350-353-355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JM/BR
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...BR
AVIATION...BR
MARINE...JM/BR
HYDROLOGY...JM/BR