000
FXUS61 KOKX 161147
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
747 AM EDT Tue May 16 2023
.SYNOPSIS...
A cold front moves through tonight followed by building high
pressure. The high shifts offshore on Thursday, but remains in
control. A frontal system impacts the area over the weekend. High
pressure builds in for the beginning of next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
The forecast is on track this morning. Only minor adjustments
were made to temperatures to capture latest obs. Otherwise, a
warm strengthening southwesterly flow is expected today ahead of
an approaching cold front. High temperatures will be back in
the upper 70s to low 80s for most, but the onshore flow will
keep eastern Long Island and southeastern CT a bit cooler as
water temperatures are still in the 50s. Given dry antecedent
conditions, low RH and gusty winds, there are fire weather
headlines today. See Fire Weather section below.
As an upper level shortwave dives down from eastern Canada with
aforementioned cold front, there will be a surge of moisture
just to our south as another weak wave jumps out ahead from our
west. Both features will have associated showers, but both look
to miss our area, one to the north and one to the south. A few
sprinkles can not be ruled out late tonight with the cold front,
but confidence was high enough to remove mention of rain
showers from the forecast.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
High pressure builds in behind the departing cold front and a cool
airmass sets up. Highs on Wednesday and Thursday will be in the 60s.
The main story in the short term period is the possibility for
frost/freeze headlines Wednesday night. Radiational cooling
conditions look great, especially across the interior. There is
some concern that the winds stay up a bit too much across the
Long Island Pine Barrens, which is usually the coldest spot on
good radiational cooling nights. Leaned heavily on the MOS
guidance and can still see temperatures trending farther down
with future forecasts. Current forecast has 31-34 across the far
northern interior. Capped the Pine Barrens at 37 for now due to
the winds. Widespread frost is not expected due to how dry we
will be (Max RH values at night 50-60 percent), but added
patchy frost where lows are 36 degrees or colder. Frost/freeze
headlines are possible across the interior and have mentioned
this in the HWO.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Dry weather expected through Friday as high pressure slides remains
situated off the Northeast coast Thursday night through Friday. night
could see some 30s as the high is progged to build right over the
area allowing for lgt winds in a dry airmass. With a southerly flow
over the area, warm advection continues Thursday night, and
temperatures are expected to warm as compared to Wednesday night,
with lows ranging from the lower 40s inland, to the lower 50s across
the New York City metro area. With the high offshore, daytime
temperatures will also be on a slow warming trend Friday and through
the weekend. Humidity levels will also be on the rise somewhat as
dew points climb into the 50s over the weekend.
A cold front is expected to move through over the weekend. There are
some timing and intensity issues to be worked out at this stage, so
NBM pops were generally used. There is a potent upper low forcing
the system, and some moisture transport from the Atlantic that may
move into the region during the day Saturday, so at least some rain
is expected with the system. Timing right now is late in the day
Saturday into Sunday, but this could change as we draw closer to the
event.
A 1020s to around 1030 high builds near Quebec on Mon, so a
dry fcst for the cwa along with seasonal temps fcst attm.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
High pressure along the Mid Atlantic coast retreats offshore today.
Meanwhile, a cold front approaches from eastern Canada and moves
through the terminals this evening.
VFR conditions are expected through the TAF period.
SW today with gusts developing around midday, 15Z-17Z. There is
greater uncertainty with the seabreeze this afternoon due to a well-
mixed airmass and stronger/deeper westerly wind. Winds likely remain
SW during the afternoon, with gusts 20-25 kt. Isolated gust of 25-
30kt possible. Gusts diminish around sunset 23Z-01Z and then shift
to the W and NW with sustained winds of around 10 to 15 kt, with
gusts OF 20-25 kt coming back into the picture for most
terminals 08Z-10Z tonight, just before and after the cold
frontal passage as winds shift more to the N.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled amendments expected. Isolated gusts of 25 to 30 kt
possible this afternoon.
OUTLOOK FOR 12Z WEDNESDAY THROUGH SUNDAY...
Wednesday: VFR. NW wind 15 to 20 kt.
Thursday and Friday: VFR.
Saturday: Chance of MVFR in showers, mainly late in the day.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
A Small Craft Advisory remains in effect for the eastern two ocean
zones. There may be several hours this morning where conditions are
just below criteria, but a southwesterly flow picks up quickly late
this morning. The Advisory gets expanded to include the western most
ocean zone, the eastern Sound and the Long Island Bays at 2pm today.
These zones then drop at 8pm, with 6 more hours of the SCA on the
eastern two ocean zones. Overall the conditions will be real
marginal, with 25-29 kt gusts and 5-7 ft waves on the ocean.
With high pressure building in behind a departing cold front,
conditions will remain below SCA through Friday night. Waves on
the ocean water build in response to a strengthening S to SE
flow, with 5 ft seas possible by late morning Saturday into the
afternoon. Although waves diminish late Saturday night into
Sunday afternoon on the ocean, wind gusts of up to 25 kt Sunday
afternoon into Sunday evening as a cold front moves through and
high pressure builds in.
&&
.FIRE WEATHER...
The Fire Weather Watch across CT for Tuesday has been upgraded to a
Red Flag Warning. A Fire Weather Watch remains in effect for
Wednesday. For northeast NJ, NYC, Long Island and the Lower
Hudson Valley an SPS has been reissued.
Given antecedent dry conditions along with Min RH values between 20
and 30 percent and a gusty flow at 20-25 kt, there is an elevated
potential for fire spread.
&&
.HYDROLOGY...
There are no hydrologic concerns through early next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Red Flag Warning until 8 PM EDT this evening for CTZ005>012.
Fire Weather Watch from Wednesday morning through Wednesday
evening for CTZ005>012.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 2 PM this afternoon to 8 PM EDT this
evening for ANZ332-340-345-355.
Small Craft Advisory until 2 AM EDT Wednesday for ANZ350-353.
&&
$$
SYNOPSIS...JP/JT
NEAR TERM...JT
SHORT TERM...JT
LONG TERM...JP
AVIATION...JP
MARINE...JP/JT
FIRE WEATHER...
HYDROLOGY...JP/JT