751
FXUS61 KOKX 292344
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
744 PM EDT Thu Aug 29 2024
.SYNOPSIS...
High pressure to our north shifts east tonight with a lingering
surface ridge into Friday night. A warm front moves through on
Saturday and then is quickly followed by a cold frontal passage
Saturday night. A secondary cold front moves through late Sunday
into Sunday night. Thereafter, Canadian high pressure builds in
and will remain in control through at least the middle of next
week.
&&
.NEAR TERM /THROUGH FRIDAY/...
The forecast is on track this evening. Showers remain west of
the area for now. With high pressure building in from the north,
any showers or isolated thunderstorms will have to battle some dry
air that is building into the area.
Otherwise, high pressure to our north shifts east tonight. It
brings a short wave ridge at the surface and lingers it over the
area through Friday. To the west, a small shortwave trough
embedded within a longwave ridge aloft brings positive vorticity
advection aloft tonight into tomorrow.
With ample moisture in place north and west of NYC, this could
lead to the development of isolated to scattered showers tonight
into the day tomorrow. Most CAMs agree on scattered showers
tonight in the Hudson Valley, SW CT and NYC metro, then taper
those chances eastward. These will originate from a line of
showers and thunderstorms that are currently developing across
central Pennsylvania. There is much disagreement among the CAMs
on the extent of shower coverage and timing tomorrow during the
day. Have gone with slight chance for much of the area tomorrow,
opting to only go chance for far west and southwestern areas
where there is somewhat more agreement on placing of showers.
Instability will be low, so any chances of thunder have been
dropped out of the forecast for tonight and tomorrow. Overall,
the POP forecast is low confidence and may be followed by
adjustments as confidence increases.
Temperatures will remain mild tonight in the low/mid-60s with
dewpoints lower near 60. Tomorrow will see plenty of cloud cover
with mild highs in the low/mid-70s, a few degrees cooler than
observed on on Thursday.
&&
.SHORT TERM /FRIDAY NIGHT/...
A small shortwave trough aloft exits east Friday night along with a
surface ridge. This will lead to tapering showers, which will lead
to dry conditions prior to sunrise and around daybreak on Saturday.
Saturday night will remain mostly cloudy-to-overcast with lows in
the low-to-upper-60s.+
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
Bit of a tricky PoP forecast to start on Saturday. A lingering
surface ridge will be extended into the area from departing offshore
high pressure. Aloft, shortwave ridging will also be moving through.
The surface ridge from the offshore high looks to hold off the warm
front early Saturday, but if the ridge breaks down earlier, the warm
front may be able to advance faster. If this happens, rain showers
will be possible earlier than the current forecast shows for
Saturday morning.
Most of the action for the weekend looks to come Saturday evening
and overnight ahead of and along a cold front. This timing continues
to be favorable for us, as instability will be lower overnight due
to the loss of daytime heating. However, pwats in the latest NAM and
GFS are both still around 2 inches right ahead of the cold front.
So, any showers or thunderstorms that move through have the
potential for heavy downpours. The bulk of the showers and
thunderstorms will be done Sunday morning, but a secondary cold
front moves through, so PoPs linger into Sunday evening.
Thereafter, Canadian high pressure builds into the area and brings a
cool and dry airmass to the region, with sunny conditions. On
Monday, dewpoints drop into the 40s and will stay there through
midweek. Temperatures will be below normal for early September
during most of next week.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
High pressure across eastern Canada into coastal New England,
and the mid Atlantic will remain in place into Friday.
Low confidence forecast with MVFR ceilings, especially at the
coastal terminals into KEWR and KTEB, with VFR possible this
evening. Then for the overnight hours, after 05Z, MVFR
conditions are expected to prevail, except possibly KGON where
VFR may remain mostly of the overnight. Low confidence with the
ceilings through Friday, and timing of VFR conditions. There is
a chance that MVFR prevails most of the day. Scattered showers
are possible overnight across the western terminals. Another
round of showers possible Friday afternoon.
An easterly flow persists through the forecast period, generally
less than 10 kt.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Low confidence in the timing and duration of showers and MVFR
conditions overnight into Friday morning. Low confidence with
ceilings through the day Friday, with the possibility of MVFR
remaining much of the day.
OUTLOOK FOR 00Z SATURDAY THROUGH TUESDAY...
Friday night: MVFR, with a chance of VFR early.
Saturday: VFR. MVFR or lower possible in showers and
thunderstorms during the evening and overnight.
Sunday: Mainly VFR. Chance of showers, mainly in the morning.
Monday and Tuesday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Winds and waves will remain below SCA criteria this week,
weekend, and through the middle of next week. There could be a
period of occasional 25 kt gusts this weekend and on Monday with
two cold frontal passages, but this remains a low probability
at this time.
&&
.HYDROLOGY...
Any hydro impacts over the weekend appear minimal at this time.
&&
.TIDES/COASTAL FLOODING...
The moderate risk of rip currents continues on Friday, with the
easterly flow continuing, but closer to 12 to 14 knots. Given the
easterly flow, rip current activity will be enhanced along jetties
and groins.
On Saturday, the flow becomes southerly, just under 10 knots. 1 ft
long period southeasterly swell does build into the area, but
thinking low risk of rip currents for now with RCMOS showing
lowering probabilities into Saturday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...BR/JT
NEAR TERM...BR/JT
SHORT TERM...BR
LONG TERM...JT
AVIATION...MET
MARINE...BR/JT
HYDROLOGY...BR/JT
TIDES/COASTAL FLOODING...