688
FXUS61 KOKX 211711
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
111 PM EDT Mon Oct 21 2024
.SYNOPSIS...
High pressure remains in control through Tuesday. A cold front
approaches on Wednesday, moving through Wednesday night into
early Thursday. High pressure builds on Thursday into Friday.
Another frontal system may move across the area this weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
Forecast on track with mainly clear skies and temperatures in
the hourly forecast database tracking very close and right at
the obs.
A large upper level ridge continues to build over the eastern
United States into this afternoon. The core of the surface high
will lie just to our south allowing for a W-SW flow in the
middle levels and the continuation of an unseasonably warm air
mass for the late October. In fact, today will likely end up the
warmest day in the current warm pattern. The previous forecast
went with the upper end of the NBM ensemble MaxT distribution
(95th percentile) and see no reason to change from this
thinking. Highs for today will likely reach the lower 80s in NE
NJ and portions of NYC with middle to upper 70s elsewhere. A few
record highs are possible. See climate section below for
current record highs for October 21st.
Another tranquil night is expected tonight with mostly clear
skies. It will not be as cool as previous nights with lows only
falling into the upper 40s for interior locations and lower to
middle 50s elsewhere. The NYC metro may not fall below the lower
60s.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The axis of the upper ridge will slide east on Tuesday and
should be offshore Tuesday night. This will allow the surface
high to move offshore as well. It will still be unseasonably
warm on Tuesday, but highs should be a few degrees lower
compared to Monday due to developing onshore flow as the high
moves offshore. Highs look to be near 80 degrees in NE NJ with
middle to upper 70s elsewhere.
Heights will fall Tuesday night with a weak shortwave lifting
across the northeast. A more organized shortwave will then pass
through the Great Lakes on Wednesday and then lift across the
region Wednesday night. A cold front will accompany the
shortwave, which likely moves through the region late Wednesday
night. The system will have little moisture to work with and any
organized forcing looks to pass to our north. For these
reasons, have removed PoPs Wednesday night consistent with the
latest NBM deterministic.
Unseasonably warm temperatures continue Tuesday night and
Wednesday. A stronger southerly flow Wednesday will prevent
temperatures from rising as much as Monday and Tuesday with
highs generally in the lower to middle 70s. Temperatures start
to come down Wednesday night, but any noticeable air mass
change occurs after the front moves offshore around day break
Thursday.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
Following the cold frontal passage from Wednesday night/early
Thursday morning, surface high pressure will build in from the
Great Lakes region through the day Thursday. This surface high
will then remain over the area on Friday. This happens in tandem
with a building ridge aloft that centers over us on Friday.
A gusty NW is expected on Thursday before they gradually subside
into Thursday night when the pressure gradient weakens. Dewpoints
will drop on THursday with sunny skies expected. Highs on Thursday
will be noticeably cooler compared to Wednesday. Highs will be in
the mid-60s to upper-50s on Thursday followed by a cool night in
the mid-30s to mid-40s. Some of the areas more susceptible to
radiational cooling could drop lower than currently forecast, if
the the winds weaken quicker than anticipated. Friday is much
the same with highs in the upper-50s to lower-60s.
Another frontal system looks to impact us Saturday morning into
Saturday afternoon followed by high pressure for the rest of the
weekend and to start next week. The upper-level trough associated
with this system is expected to deepen over us into Saturday night
before moving east into Sunday. We`ll be sandwiched between the
deep trough to the east and a building ridge to the west on
Sunday before the ridge centers closer to our area on Monday.
We`ll still be too dry for rain to occur with this cold front, but
do expect building cloud cover ahead of the front on Friday night
before cloud cover moves out late on Saturday. This along with a
returning southerly flow will lead to a slightly warmer night
Friday night with lows in the low-50s to low-40s.
A tightening pressure gradient between the low to our northeast
and a high to our west on Saturday into early Sunday could lead
to breezy NW flow before the pressure gradient relaxes into
Sunday night.
Given the front comes with a deep trough and persistent NW flow,
we can expect colder temperatures to prevail this weekend.
Highs on Saturday will be in the mid-60s to low-60s, dropping to
the mid-40s to mid-30s Saturday night. Then Sunday afternoon
will be noticeably colder with highs in the upper-50s to low-50s
followed by near- freezing temperatures Sunday night in the
interior and low-40s for the rest of the area.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
-- Changed Discussion --
High pressure remains in control, drifting off the northeast
and mid Atlantic coast during Tuesday.
VFR.
Generally a light SW flow, 5 to less than 10 kts through this
afternoon, with a late day sea breeze possible at KJFK. Winds
become light and variable this evening, and then light south by
late Tuesday morning.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled amendments expected. A late day sea breeze
possible at KJFK, with winds 200 around 9kt 20Z/21Z.
OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...
Tuesday through Saturday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
High pressure and a weak pressure gradient will lead to winds
and seas below SCA levels through Tuesday night. A cold front
approaches on Wednesday and moves across the waters Wednesday
night. Conditions will remain below SCA levels, but wind gusts
could approach 20 kt, especially the ocean, Wednesday night.
SCA wind gusts are possible on ocean waters Thursday afternoon
and evening. Ocean seas may also build to around either 4 or 5
ft during this timeframe. Winds and seas subside Thursday night,
and sub small craft advisory conditions are then expected on
all waters.
&&
.FIRE WEATHER...
Dry weather continues this afternoon with Minimum RH will be
between 25 and 35% for most of the area leading to conditions
conducive for fire development, should ignition occur. Winds
will be light, lowering concerns of fire spread overall.
&&
.HYDROLOGY...
There are no hydrologic concerns through the upcoming weekend.
&&
.CLIMATE...
Record highs are possible today. Here are the current record
highs for October 21st.
EWR: 84/1947
BDR: 78/1963
NYC: 84/1920
LGA: 82/1947
JFK: 81/1963
ISP: 76/2017*
*Also in other years
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...BR/DS
NEAR TERM...JE/DS
SHORT TERM...DS
LONG TERM...BR
AVIATION...MET
MARINE...BR/DS
FIRE WEATHER...
HYDROLOGY...BR
CLIMATE...