000
FXUS61 KOKX 161855
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
255 PM EDT Mon Oct 16 2023
.SYNOPSIS...
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After one trough passage this evening, another one approaches
Tuesday and moves across Tuesday night. High pressure builds in
for the middle of the week. High pressure along the eastern
seaboard early Thursday moves into the western Atlantic as a
frontal system approaches to the west. This system impacts the
region Friday through Sunday.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH TONIGHT/...
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Seeing how well these CAMs perform with reflectivity forecasts,
with multiple CAMs indicating scattered shower development this
afternoon. Current radar imagery is quite similar to CAMs with
respect to reflectivity. Forecast updated for isolated to
scattered rain shower coverage. Much of these rain showers are
expected to be light without much, if any, reduction in
visibility.
Temperatures were also adjusted slightly up from previously
forecast to better match with observed trends. Otherwise, rest
of forecast mainly on track.
The shower activity is associated with a surface and upper level
trough and enhanced lift ahead of the trough axis as diagnosed
by positive vorticity advection.
With the first trough moving across, still cannot rule out a brief
light rain shower or sprinkle this evening. The mid level trough
axis moves across this evening and by overnight will be southeast of
the region with its maxima of positive vorticity advection.
While moisture will remain limited, any enhancement to lift as
diagnosed from positive vorticity advection will trend down this
evening. Some models even exhibit some negative vorticity
advection tonight.
CAMs with their forecasts of reflectivity decrease in coverage by
mid to late evening. Expecting any brief light rain showers or
sprinkles to taper off during the evening with dry conditions
expected overnight.
Lows tonight a combination of MOS and NBM, ranging from the lower
40s to lower 50s.-- End Changed Discussion --
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The upper trough will remain over the region on Tuesday, and
will gradually lift out to the NE, with building heights and
surface high pressure for the middle of the week.
The short term period will remain dry, with a partly to mostly
cloudy day on Tuesday. Surface high pressure then builds across
the area Tuesday night and Wednesday with plenty of dry weather
and temperatures starting to warm a few degrees.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
An amplifying upper trough over the upper midwest into the mid
Mississippi Valley tracks eastward Thursday and deepens into a
full latitude trough by Friday morning. The trough becomes
negative and tracks slowly northward along the coast through
next weekend. The likelihood of precipitation for next weekend
has increased with probabilities likely to near categorical as
energy rotating through the upper trough develops a secondary
surface low along the southeastern coast Friday night that
deepens through Saturday while tracking northward. With the
intensifying low a strong and gusty west to northwest flow
develops as the low moves to the northeast of the region
Saturday night into Sunday. With more certainty in
precipitation this upcoming weekend, this would be the the 7th
consecutive weekend of rainfall being recorded at Central Park.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
Low pressure continues moving across the Canadian Maritimes
into tonight. High pressure begins building over the northeast
on Tuesday.
VFR. A few sprinkles or light showers are possible this
afternoon and evening.
NNW-N winds 10-15kt this afternoon will begin to diminish below
10 kt this evening. A light NNW-N flow then prevails overnight,
with most outlying terminals becoming light and variable. Light
NW winds 10 kt or less are expected on Tuesday.
....NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Wind direction may vary 20-30 degrees from forecast at times
this afternoon and early evening.
An occasional gust 15-18 kt is possible this afternoon.
OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...
Tuesday Afternoon through Thursday: VFR.
Friday: Mainly VFR early, then chance of MVFR and showers late.
Showers likely with MVFR or lower possible at night. S-SE wind
gusts 20-25 kt late day and at night.
Saturday: MVFR or lower in showers early. VFR possible in the
afternoon. S-SE wind gusts 20-25 kt becoming W in the afternoon.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
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Weak ambient pressure gradient across the waters through Tuesday
night will allow for conditions to remain below SCA thresholds.
No headlines are expected on the area waters with sub-SCA
conditions forecast through the middle of the week.
A frontal system with increasing southerly flow Thursday into Friday
may result in SCA conditions on the ocean waters beginning late
Friday, and continuing into at least Saturday. By late Saturday a
west to northwest flow behind deepening offshore low pressure may
bring SCA wind gusts to the non ocean waters as well.-- End Changed Discussion --
&&
.HYDROLOGY...
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Less than a tenth of an inch is forecast with showers through
Tuesday night. No hydrologic problems are expected.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...BC/MET
NEAR TERM...JM
SHORT TERM...BC/JM
LONG TERM...MET
AVIATION...DS
MARINE...BC/JM/MET
HYDROLOGY...JM/MET