000
FXUS61 KOKX 161723
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
123 PM 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/...
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 generally be in the mid and upper 70s, with a
a few lower 80s possible across the NYC metro. 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 /17Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
VFR. A cold front approaches and moves through the terminals
this evening.
SW winds with isolated gusts of 20-25kts possible. Gusts should
then diminish around sunset 23Z-01Z and then shift to the W and
NW with sustained winds of around 10-15kts through the
overnight. Gusts of 20-25 kt then return after 08Z 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.
Sunday: Chance MVFR in early showers.
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 then expands 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.
Marginal SCA conditions are also possible following the cold
frontal passage tonight into Wednesday. Confidence is not high
enough to issue at this time and will evaluate incoming
guidance for the potential.
Otherwise, 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...
A Red Flag Warning remains in effect for CT today, with a Fire
Weather Watch in effect for Wednesday.
For northeast NJ, NYC, Long Island and the Lower Hudson Valley
an SPS was been issued,
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...
-- Changed Discussion --
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 until 8 PM EDT this evening for ANZ332-
340-345-355.
Small Craft Advisory until 2 AM EDT Wednesday for ANZ350-353.-- End Changed Discussion --
&&
$$
UPDATE...DW
AVIATION...DBR