000
FXUS61 KOKX 191750
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
150 PM EDT Tue Mar 19 2024
.SYNOPSIS...
Weak high pressure will be in control through early
Wednesday as a weak trough passes offshore. A cold front then pushes
through the region on Wednesday. High pressure then settles
over the region Thursday into Friday ahead of a frontal system
and associated low pressure Friday night into Saturday. High
pressure should then return Sunday into early next week.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
The forecast is mainly on track with minor updates made to some
of the hourly forecast elements. A zonal mid level flow remains
this afternoon with high pressure located to the southwest of
the area. Surface winds backing more WSW this afternoon,
coinciding with increased cloud cover from the west this
as mid level moisture advection increases in association with an
approaching weak mid level shortwave. Given the dry low levels
and weak lapse rates, not expecting any measurable precipitation,
but still cannot rule out a stray flurry or sprinkle mainly N
and W of the city, especially as we near the end of the afternoon.
Wind gusts will be gusting mostly 25-35 mph with a few gusts
35-40 mph possible. High temperatures near or just below
normal, in the upper 40s to near 50 per NBM.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
Aforementioned zonal flow becomes more amplified as a closed mid and
upper low over Quebec sends a trough though the region on Wednesday.
At the surface, low pressure heading northeast from Ontario into
Quebec by Wednesday afternoon will drag a cold front through the CWA
by Wednesday evening. Shower chances increase by afternoon as the
front approaches. The system does not have a lot of moisture to work
with, with PW less than 0.25" and thermal profiles suggestive of
light rain showers at best for most of the area. The one exception
may be across far northwestern sections, NW Orange and Putnam
counties, where some snow showers may mix in very briefly at the
end. Highs tomorrow a few degrees warmer than Tuesday under WSW
flow, though afternoon cloud cover may mitigate somewhat depending on
how quickly they overspread.
Behind the front on Wednesday night into Thursday, dry and blustery
conditions prevail with cold air advection under gusty northwest
flow. Highs on Thursday will struggle to get into the mid 40s, with
wind chills making it feel like the low to mid 30s. Thursday AM wind
chills will feel even colder, in the teens to low 20s.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
There are still fairly significant differences among the
deterministic and ensemble models for Friday night into Saturday.
However, there is an increasing probability for a period of
unsettled conditions during this time frame.
*Key Points*
*A cold night is in store Thursday night with lows in the 20s for
most locations as high pressure settles over the region.
*Dry conditions will continue on Friday with temperatures remaining
below average in the lower to middle 40s.
*Probabilities for precipitation have increased Friday night into
Saturday. The overall pattern supports potential of a wintry mix
inland at the onset, with mainly rain into Saturday.
*Mainly dry conditions are currently expected Sunday, which should
prevail into early next week.
*Temperatures should be below normal Sunday and Monday, potentially
above normal by next Tuesday.
Upper ridging Thursday night into Friday will give way to a split
flow regime into the weekend. There will be a southern stream system
moving across the southeast on Friday. At the same time, a frontal
boundary associated with a northern stream upper trough over
southern Canada will be approaching into Friday night. The latest
modeling is still disagreeing with the amount of interaction between
the two streams as both the frontal boundary and southern low emerge
along the east coast. The modeling that shows more
interaction/phasing leads to widespread precip late Friday night
into Saturday. Other guidance with less interaction bring a period
of precip Friday night with the front, but keep the associated low
pressure well to our south. Another scenario that is depicted by
some of the latest guidance is for the southern stream to become cut-
off near southeast coast with the associated low, or pieces of the
low, nearing the LI coast into Sunday. Due to the continued large
spread in the guidance and uncertainty with both the northern and
southern stream systems, have stayed close to the NBM during this
time frame.
As noted above, PoPs have increased Friday night into Saturday.
The latest NBM probabilities for greater than 1 inch of rain in 24
hours have also increased over the last day and are now 30 to 50
percent, highest NYC on east.
High pressure should return Sunday into early next week although the
timing of this may depend on if the southern low hangs around a bit
longer than currently anticipated.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
A cold front passes late Wed.
VFR through at least 16Z Wed. Sct shwrs mainly aft 18Z could
produce brief periods of MVFR. There is a chance a few of the
shwrs cold mix with IP or SN, especially N of the NYC arpts.
WNW winds back to the W this eve and SW overnight. Winds veer a
little to the W behind the front late Wed.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Gusts could be a few kt higher at times, especially this
afternoon.
End time of gusts may be off by 1-2 hours this evening.
Winds may shift closer to 300 true around 22-23Z Wed. Timing
uncertain so no additional group was added to the TAFs attm.
OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
Rest of Wednesday: Brief MVFR possible in the afternoon and
early evening. SW winds becoming NW 22-03Z.
Thursday: VFR. NW wind gusts around 30 kt.
Friday: VFR through early evening. MVFR or lower possible
overnight with chances for rain near coast and rain/snow inland.
Saturday: MVFR or lower at times. Mainly rain likely. SE wind gusts
20-25 kt during the day, becoming NW with higher gusts at
night.
Sunday: VFR with gusty N winds.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
SCA continues on all waters through the day today. Still some
question as to how long into this evening advisory conditions
will continue to prevail. Might need to extend the SCA on the
non-oceans waters by a couple of hours into this evening. Might
also need to adjust the 06z Weds end time on the ocean.
Small craft conditions otherwise likely return for the ocean
and western near shore zones Wednesday. Gales are also a
possibility on the ocean and the nearshore waters late Wed night
and into early Thursday. Sub SCA conditions then return late
Thursday as the pressure gradient relaxes. A weakening pressure
gradient Thursday night will lead to winds beginning to fall
below SCA levels, especially late. Conditions will then remain
below SCA until late Friday night into early Saturday morning
with a return to SCA wind gusts on the ocean. This may then
spread to the non-ocean waters on Saturday and continue Saturday
night as a frontal system and low pressure move across the
waters. Ocean seas will also become elevated during this time
frame.
&&
.FIRE WEATHER...
Dry conditions are expected today with minimum RH values
averaging around 30 percent and gusts 25-30 mph. Per
coordination with surrounding offices and fire weather partners,
no special weather statements will be issued for today.
&&
.HYDROLOGY...
No hydrologic impacts are expected through Thursday. While the
chance for widespread precipitation has increased a bit over the
last 24 hours for Friday night into Saturday, no hydrologic
impacts are currently anticipated.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ331-
332-335-338-340-345.
Small Craft Advisory until 2 AM EDT Wednesday for ANZ350-353-
355.
&&
$$
SYNOPSIS...DBR/DS
NEAR TERM...JC/DBR
SHORT TERM...DBR
LONG TERM...DS
AVIATION...JMC
MARINE...DBR/DS
FIRE WEATHER...
HYDROLOGY...DBR/DS