000
FXUS61 KOKX 150533
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1233 AM EST Mon Jan 15 2024
.SYNOPSIS...
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High pressure builds to the southwest overnight and Monday. Low
pressure will approach Monday night and pass to the south and
east on Tuesday. High pressure builds from the south and
southwest Wednesday, and slides off the coast the second half of
Thursday. Low pressure develops across the deep south and lifts
northeast and approaches along and off the coast Friday. High
pressure builds next weekend.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
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Forecast remains on track. Cold and dry air continues to filer
into the region. High pressure will build to the southwest
overnight. Winds have diminished and gusts have mostly come to
an end as the pressure gradient relaxes.
Lows will be in the mid/upper teens for northern interior areas
while coastal areas will be in the lower 20s. Some areas will
be 10 degrees below seasonal normals.-- End Changed Discussion --
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
Updated PoPs for Monday night based on recent 18z and some new
00z high resolution data indicated increasing thermal forcing
and jet support for snow to break out earlier. Simulated
reflectivities a band of light snow along a baroclinic zone
lifting northward Monday night with some guidance bringing in
light snow as early as 00-03z. For now have pushed up likely
PoPs for the southern portion of the area after 06z, but this
may need to be sped up further once the rest of the 00z suite
has run. The jet support aloft and middle level thermal forcing
should be enough to overcome any lingering low level dry air.
Otherwise, the cold airmass remains in place on Monday as high
pressure builds in to the southwest and the southeastern Canada
low gradually tracks farther to the northwest. Temperatures will
remain as much as 10 degrees below normal with highs on Monday
near freezing for the southern coastal half of the CWA and highs
in the upper-20s for the northern interior half of the CWA.
Monday night will be another cold one with widespread lows in
the 20s, some teens for the far interior.
Surface low pressure developing off the SE coast Monday night
tracks northward to near the 40N/70W benchmark Tuesday
afternoon/evening. Mainly light snow should continue
overspreading the region late Monday night through day break
Tuesday aided by a strong jet streak developing aloft.
Currently expecting a total snowfall around 2-3 inches, which
will be close to Winter Weather Advisory criteria. There is
still some uncertainty as to the exact amount of snowfall. While
much of the area will keep frozen precipitation, a frozen
rain/snow mix may be possible Tuesday afternoon for southeastern
coastal areas.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
*Key Points*
* Below normal temperatures through the period. The first prolonged
stretch of below normal temperatures this winter season.
* Quick moving coastal low may bring snow to the region on Friday.
A strong negative NAO and a moderately strong negative AO pattern
through the long term. This will lead a long stretch of below normal
temperatures through the period. This adds stability to the pattern
to a degree. The uncertainty going forward relates to how much any
southern branch features interact with the polar branch of the jet
stream late in the week. Thereafter the region likely gets its first
taste of arctic air, or at least modified arctic air towards the
tail end of the period later next weekend.
As far as temperatures go, stayed fairly close to the NBM for much
of the period. However, late in the period went slightly below the
consensus guidance as the air mass that approaches out of the NW
territories of Canada should have some air of Siberian origin
entrained in it.
With a split in the Polar Vortex and anomalously low heights south
of Hudson Bay Tuesday night into Wednesday look for the coldest air
of the season to arrive. Behind departing low pressure on a NW wind
look for one of the coldest night`s thus far Tuesday night and
certainly the coldest day on Wednesday. For some perspective,
temperatures likely do not get to freezing and may not get out of
the 20s at the coast on Wednesday. Some slight temperature
moderation then likely takes place Thursday and Thursday night in
advance of the next system. There remains a good degree of
uncertainty with a system emerging out of the Gulf and SE states as
a wave along the southern branch of the jet stream pushes northeast.
Model consensus at this point has the low nudging offshore, but
there remain many ensemble members and even some deterministic
global models bringing the system close enough for the potential for
accumulating snow to the region. Some of the more westward guidance
even indicates the possibility of some mixing with rain. With the
teleconnections the way they are and a strong -NAO, and a neutral to
perhaps slightly positive mean trough late in the week, am inclined
at this point to lean slightly towards a more eastward / suppressed
track. Due to the high uncertainty stayed close to consensus / NBM
PoPs and p-types. Based on model sensitivity the outlook for the
late week system will oscillate back a forth a few times in all
likelihood. Regardless of the outcome of the late week system, in
its wake the first air mass of the season of much below normal
temperatures is likely into next weekend.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
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High pressure builds towards the terminals into this afternoon.
Low pressure develop along the East Coast tonight and tracks
southeast of the terminals on Tuesday.
VFR until around 00-03z Tue. -SN will develop and overspread the
area from south to north with MVFR or lower conditions overnight
into early Tuesday morning.
W-WNW winds 10-13 kt will continue weakening over the next few
hours, becoming 10 kt or less after 09z Mon. These winds
prevail the remainder of the morning before the wind direction
shifts to the SW in the afternoon and evening. The flow becomes
light and variable this evening.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of -SN this evening into tonight may be off by several hours.
OUTLOOK FOR 06Z TUESDAY THROUGH FRIDAY...
Late tonight: MVFR or lower in snow.
Tuesday: IFR with snow likely, tapering off in the afternoon and
evening. Some rain could mix in with the snow near the coast.
Total snowfall accumulations 1 to 3 inches.
Tuesday Night. Becoming VFR. NW wind gusts 15-20 kt.
Wednesday: VFR. W wind gusts near 20-25 kt.
Thursday: Mainly VFR. W wind gusts near 20 kt.
Friday...IFR with snow possible. NE-N wind gusts near 20 kt in the
afternoon.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
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The SCA for the non-ocean waters has been cancelled as gusts
have either ended or were below 25kt. For the ocean waters the
SCA remains in effect and is mainly for subsiding seas as
frequent gusts to SCA levels have ended. Ocean seas should
subside below 5 ft by Monday morning with Sub-SCA conditions
prevailing into Tuesday.
Small craft advisory conditions should prevail on most of the
waters Tuesday night through Wednesday night in the wake of
departing offshore low pressure. Gale force wind gusts are
possible for the eastern near shore and ocean waters during this
time with elevated ocean seas. Marginal small craft conditions
may linger out on the eastern ocean waters in Thursday, with sub
small craft conditions for the ocean Thursday night into the
first half of Friday.-- End Changed Discussion --
&&
.HYDROLOGY...
No hydrologic impacts expected through Saturday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EST early this morning for
ANZ350-353-355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JE/BR
NEAR TERM...BR/DS/MET
SHORT TERM...BR/DS
LONG TERM...JE
AVIATION...DR/DS
MARINE...JE/BR/DS/MET
HYDROLOGY...JE/BR