371
FXUS61 KOKX 131153
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
753 AM EDT Sun Oct 13 2024
.SYNOPSIS...
A warm front stall over the forecast area today. A cold front
moves through late tonight into early Monday morning. High
pressure slowly builds through mid-week. High pressure settles
over the area Friday and Saturday.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
The forecast is on track. Showers are moving in from the west
across the Lower Hudson Valley and northern New Jersey in
association with approaching low pressure from the west.
A warm front to the south will slowly move northward today, stalling
over the region by mid to late this morning. At the same time, an
upper level trough dives south from the western Great Lakes region
and aids in some intensification of this low over the Northeast.
Most of the deterministic models show the low intensifying as it
rounds the base of the trough and heads into northern New England. A
period of light rain showers is therefore in the forecast today
through tonight. Much of the rain will generally be limited to
northeast NJ, the Lower Hudson Valley, and southern CT as the
stalled front bisects the area. Slightly more stable air to the
south of the warm front will mean less in the way of showers until
the cold front approaches and moves through tonight. In fact, some
models show mainly dry conditions for NYC and much of Long Island
today through tonight, so it`s quite possible that some areas remain
dry. There is also a brief period window for the possibility of
thunder for the first half of Sunday night as instability aloft
increases to a couple hundred J/kg, so continue to carry a slight
chance for thunder from 2 am to 8 am Sunday night into Monday
morning.
There continues to be a bit of a temperature gradient across the
forecast area today, with area north and west of NYC seeing highs in
the lower 60s, while the city and coastal areas see highs in the
upper 60s to middle 70s. This is because the frontal boundary is
expected to be within the forecast area today. However, there is a
large spread in temperatures seen in the NBM for today (as much as
11 degrees in some cases) as there is uncertainty in where the
frontal boundary will be. If it ends up farther north than is
currently forecast, then temperatures will likely be warmer than
what is currently in the forecast. If it remains to the south, then
cooler temperatures can be expected.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
A slight chance for showers Monday morning with a cutoff low over
the Northeast providing some weak lift and some steep lapse rates
noted in the forecast soundings in the lowest levels of the
atmosphere, but much of any showers will occur north of the area,
closer to the cutoff low. As the low treks farther northeast,
chances for showers fall, so dry conditions expected everywhere by
Monday afternoon.
Highs on Monday will be seasonable, ranging from the upper 50s
inland, to the upper 60s along the coast. With the strengthening low
pressure to the north and the high building in, a strong pressure
gradient will set up over the area, and breezy conditions are
expected, with gusts of 20 to 30 mph.
Continued cold advection through Tuesday as the upper low spins over
northern New England and southeastern Canada will mean even cooler
temperatures for Tuesday. Highs are not expected to climb above the
50s, with overnight lows Monday night into Tuesday in the middle to
upper 30s away from the coast, and in the lower to middle 40s along
the coast. Winds remain above 5 kt at night, so this will preclude
the formation of frost.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A slow moving, positively tilted upper trough will linger over the
region on Wednesday, then start to pull away on Thursday. This will
induce sfc cyclogenesis well offshore, and also prevent high
pressure to the west from building in too quickly. Once the trough
pulls away and heights rise aloft, the high to the west should build
in more strongly and settle over the area later this week.
This pattern will usher in the coolest air mass of the season, with
well below normal temperatures on Wednesday (highs only in the 50s)
and then gradually moderating daytime temps after that under mostly
clear skies. With that plus fairly light winds, most nights will
radiate well, with lows in the 30s inland and 40s coastal/metro
areas, and frost inland especially Wed night and Thu night.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
A warm front will approach from the south. This will bring in bkn
VFR cigs which may linger for much of the day especially inland, and
there could be a few showers early this morning and again this
afternoon near KSWF, then late today into this evening
throughout.
E-NE winds less than 10 kt should become SE 5-10 kt at the
metros by afternoon, then S around 10 kt late, with some
uncertainty whether gusts up to 20 kt will materialize when
winds become S. LLWS likely at the metros as SW winds increase
to 40-45 kt at FL020.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled AMD expected.
OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...
Monday: VFR with any showers ending in the morning. NW winds
10-15G20kt in the morning, becoming W-NW 15-20 kt with gusts
25-30kt in the afternoon, then NW 10-15G20kt by late eve.
Tuesday and Wednesday: VFR. W-NW winds 10-15G20-25kt.
Thursday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
With an increasing southerly flow behind the warm front and an
increased pressure gradient as the low approaches and tracks
across the region Sunday night and northeast Monday, wind gusts
and ocean seas are expected to reach SCA levels by midday
today. Also, the southerly wind gusts across the south shore
Long Island bays will be near 25 kt. Gusts diminish on the back
bays by around midnight or just after midnight Monday and SCA
is in effect until 2 am Monday morning.
With a strong and gusty northwest flow developing Monday behind
the cold front and low, small craft gusts are likely across all
the forecast waters, therefore issued SCA for all waters from
mid morning Monday through 11 pm Monday night. Ocean waters will
continue to see wave heights above 5 ft through at least 2 am
Tuesday, so extended the SCA for the ocean waters until then.
Quiet for Wed and Thu as high pressure slowly builds
eastward toward the waters and the pressure gradient gradually
relaxes.
&&
.HYDROLOGY...
There are no hydrologic concerns through the start of next
weekend.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 11 AM to 11 PM EDT Monday for ANZ331-
332-335-338-340-345.
Small Craft Advisory from noon today to 2 AM EDT Monday for
ANZ345.
Small Craft Advisory from noon today to 2 AM EDT Tuesday for
ANZ350-353-355.
&&
$$
SYNOPSIS...BG/JP
NEAR TERM...JP
SHORT TERM...JP
LONG TERM...BG/JP
AVIATION...BG
MARINE...BG/JP
HYDROLOGY...BG/JP