521
FXUS61 KOKX 101730
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
130 PM EDT Thu Oct 10 2024
.SYNOPSIS...
High pressure will be in control for the next few days with only a
dry cold front passing through on Saturday. A frontal system
then impacts the region Sunday into Monday with a strong cold
front moving through Sunday night into Monday morning. High
pressure then builds in through Wednesday.
&&
.NEAR TERM /THROUGH TONIGHT/...
The fcst is on track with no major changes. High pressure
builds in at the surface and aloft through tonight. Dry and
mostly clear through the period with a breezy NW flow
diminishing tonight. Still thinking that there will be patchy
frost across some of the northern zones, but not enough
widespread coverage across any of the zones to warrant an
advisory. Although dewpoint depressions would be just low enough
to support frost, formation will probably be limited to areas
where the wind decouples from the flow aloft - which will still
be greater than 10kt near the top of boundary layer. Best chance
for something more than patchy frost and potentially need an
advisory would be over Orange County, where decoupling would
more likely occur due to less of a pressure gradient. After
collaboration with the surrounding offices, will hold off on any
advisory issuance for the time being.
NBM looked good for high temperatures today, but for lows, blended
in MAV/MET MOS for locations that are more prone to radiational
cooling. Highs only in the upper 50s to lower 60s. Lows will range
from the mid-upper 30s inland to the 40s along the coast.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
The flow aloft slowly flattens Friday into Saturday, sending a cold
front through the region during the day Saturday. Continued dry
weather in spite of the cold front as there will be a lack of
moisture enhanced by a deep W to NW flow. This flow will also factor
into above-normal temperatures with downsloping and compressional
heating. NBM looked good for highs on Friday, but still thinking NBM
is too cool for high temperatures on Saturday given the setup and
timing of the frontal passage. Have therefore bumped up the
deterministic NBM by a few degrees in most spots. Highs in the upper
70s for the typically warmest spots in NE NJ and some areas in the
city, with lower to middle 70s elsewhere. Clouds increase late
Saturday night ahead of the next system, but it appears that we
should remain rain-free through the night.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
A northern stream system will move across the region Sunday night
into Monday. It will be an amplifying trough evolving into a closed
low over southern Canada into the northern Great Lakes, and
amplifying into the upper midwest. This system continues to deepen
along the eastern coast into the middle of next week. At the
surface, a frontal boundary south of the area moves back north as a
warm front on Sunday. The cold front moves through sometime Sunday
night into Monday morning, though there is still some timing
differences between models. This cold front will bring in colder air
on a gusty northwest flow. With the timing differences have used the
NBM probabilities. Cold high pressure builds in behind the front
Monday night into Wednesday.
Temperatures will be 5 to 10 degrees below normal Monday through
Wednesday. With the cold air moving in patchy frost is possible
across the lower Hudson Valley Monday night and Tuesday night.
However, NBM shows greater than a 50% chance of winds greater than 5
mph Monday night into Tuesday, which might be strong enough to
prevent the formation of frost in most places, so there is still a
great deal of uncertainty this far out with winds and
temperatures.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --
High pressure builds in through Friday morning, and settles nearby
late in the day.
VFR through the TAF period.
NW winds at 10 to 15 kt, with gusts 20-25 kt for this afternoon.
Gusts may be a few kt weaker than is forecast. Gusts end this
evening and the winds remain NW overnight at primarily 5 to 10 kt,
but closer to 5 kt for the non-city terminals.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled amendments expected.
OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY...
Friday afternoon: VFR. W winds, becoming SW late for some terminals.
Saturday: VFR. W-WNW winds G15-20kt during the day.
Sunday: VFR for much of the day, SE / S winds G15-20kt in the
afternoon. Chance of showers with possible MVFR late and mainly at
night.
Monday: Mainly VFR, brief MVFR possible early in showers. W to NW
winds 10 to 15 kt, with gusts 15 to 20 kt.
Tuesday: VFR. NW winds.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
NW flow diminishes a little this afternoon then picks up slightly,
mainly over the eastern waters, late in the day into the
evening. There could be occasional gusts to 25kt over the ocean
waters east of Fire Island Inlet later this afternoon and
evening, but the anticipated frequency of this is not enough
issue an advy attm. Sub-advisory conditions are otherwise
expected through Friday. There is then a good chance of a period
of advisory conditions is Friday night into Saturday on the
ocean with the approach and passage of a cold front.
Winds and seas remain below advisory levels through Sunday. Then
southerly winds ahead of the next cold front will increase late
Sunday into Sunday night and ocean seas are likely to build to 5
feet Sunday night, with gusts marginal near 25 kt. Small craft
conditions continue on the ocean waters into Monday night with a
cold frontal passage late Monday. Waves fall below 5 ft on Tuesday
and wind gusts generally fall below 25 kt, but marginal SCA gusts
may still be possible, especially on the ocean waters.
&&
.HYDROLOGY...
There are no hydrologic concerns through the middle of next
week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...None.
NJ...None.
MARINE...None.-- End Changed Discussion --
&&
$$
SYNOPSIS...JC/JP
NEAR TERM...JMC/JC
SHORT TERM...JC
LONG TERM...JP
AVIATION...JE
MARINE...JC
HYDROLOGY...JC/JP