okx-afd on 2025-01-12

158
FXUS61 KOKX 121447
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
947 AM EST Sun Jan 12 2025

.SYNOPSIS...
High pressure settles over the northeast today and then
weakens tonight into Monday. A cold front will pass across
the area Monday night followed by high pressure slowly building
from the west Tuesday through the end of the week. A complex
frontal boundary works through next weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --Increased cloud coverage towards westernmost parts of the
forecast region, within Western Passaic County NJ and Orange
County NY this morning. Otherwise, mostly sunny sky conditions
are expected today. Also slightly increased temperatures.
Otherwise, forecast remains on track.

Ridging builds overhead both aloft and at the surface through
this afternoon. This will lead to dry conditions along with
diminishing winds. Skies will be mostly clear to start the day.
There may be a slight increase in mid clouds in the afternoon as
some moisture starts pushing eastward ahead of digging upper
low towards the Northern Plains and Great Lakes. High
temperatures will likely be slightly above normal in the upper
30s to lower 40s.

The surface high weakens tonight and shifts southeast as the
upper ridge axis moves offshore. Middle level shortwave energy
ahead of the aforementioned upper low moves through which will
bring mostly cloudy skies. The clouds should move east just
before day break. No precipitation is expected the subcloud
layer remains dry and the lift is very weak. Lows will fall into
the 20s across much of the area with the NYC metro around 30
degrees.-- End Changed Discussion --

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
The upper low and its associated surface low moves across
southeastern Canada Monday into Monday night. This will send
a cold front across the area by Monday evening, which will
likely be offshore around day break Tuesday. A trailing
shortwave and its associated middle level energy swing across
late Tuesday into Tuesday night.

Dry conditions are expected Monday through Tuesday night.
Temperatures on Monday will be slightly above normal and
generally in the low 40s. There may be some periods of
scattered to broken clouds, especially as the cold front
approaches. These clouds should diminish Monday night behind the
front and with increasing cold/dry advection. There does not
appear to be a drastic temperature drop behind the front, but
temperatures should bottom out in the lower to middle 20s by
Tuesday morning. NW winds will also begin increasing with gusts
20-25 mph expected Monday night.

Blustery and cold conditions are likely on Tuesday as the
region lies between building high pressure to the west and low
pressure towards the Maritimes and North Atlantic. NBM
deterministic winds have been running too low in similar set ups
with NW flow and cold advection. Have bumped up winds and wind
gusts closer to the NBM 90th percentile, and these may need to
be adjusted a up a bit more in subsequent forecasts. The low
level flow and winds atop the mixed layer do not look as strong
as what was observed last week. The NW flow, cold advection and
subsidence should allow winds to reach 15- 20 mph with gusts
25-35 mph. A few gusts up to 40 mph are possible, especially
near the coast. It may take some time for the winds to come up
on Tuesday with peak winds occurring late in the day and at
night once the shortwave moves across the area and the pressure
gradient tightens. High temperatures will be below normal in the
upper 20s inland to the lower 30s closer to the coast. Wind
chills look to be in the teens to around 20 during the day, but
then fall to the single digits Tuesday night with actual lows in
the teens to low 20s.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Key Point(s)

* Dry, brisk, and cold weather with below normal temperatures
  prevails Wednesday and Thursday.

* Temperature moderation late week.

* Frontal boundary likely to approach next weekend with the our next
  round of measurable precipitation.

Trough in the East and Ridge out West large scale pattern
generally holds for the foreseeable future. Although the
eastern trough is likely to pull back further west Friday into
Saturday. This should allow temperatures to turn milder, at
least temporarily.

The main story for this period will be the return of brisk, at
times windy conditions for mid week. Some single digit wind
chills are likely Wednesday morning, especially across far
northern and northwestern portions of the area. Went above the
consensus wind guidance on Wednesday as the region will be in
the wake of a potent shortwave and strong mixing and a strong
pressure gradient in place should allow wind gusts to approach
30 to 35 mph during the daytime keeping wind chills in the
teens. A high pressure ridge then settles across with the
pressure gradient relaxing Wednesday night into Thursday with
lighter winds. Dry conditions should continue into Friday with
the high pressure ridge moving across. The ridge then gets
offshore Friday night. A milder southerly flow should actually
get temperatures above normal Friday night. A southerly flow out
ahead of the cold frontal boundary may allow temperatures to
slowly rise Friday night, especially late as more cloud cover is
expected to arrive. Have increased PoPs into the day Saturday.
An elongated southerly fetch ahead of the boundary should allow
any precip to be mainly in the liquid form, although far NW
interior locations may begin as a wintry mix. The boundary is
expected to move off to the east later in the weekend with drier
air and eventually colder air likely to return late in the
weekend.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --VFR as high pressure builds from the west today and remains in
place tonight.

Mainly NW winds at or just under 10 kt at most terminals should
lighten this evening and remain light westerly, to light and
variable later tonight.

 ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

No unscheduled amendments expected.

OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...

Monday: VFR.

Monday night: VFR. W winds G15-20 kt developing.

Tuesday through Wednesday: VFR. NW winds G20-30 kt, diminishing
Wed night.

Thursday: VFR.

Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --With gusts on a downward trend this morning, and gusts staying
near or under 20 kts as well as downward trend in ocean seas,
cancelled the SCA across the ocean.

Conditions will remain below SCA levels through tonight.
Conditions should remain below SCA on Monday, but winds on the
ocean may approach 20 kt ahead of a cold front. Behind the
front, NW flow increases with SCA conditions likely Monday night
through Tuesday night. Gale potential appears low on
Tuesday/Tuesday night, but if the flow ends up stronger than
expected, gales could become more likely especially Tuesday
night.

Small craft conditions should carry through the day Wednesday and
possibly into the evening. A period of gales are possible on the
ocean on Wednesday. Conditions are then expected to settle down to
sub advisory levels by early Thursday morning. Sub advisory
conditions should last into Friday.-- End Changed Discussion --

&&

.HYDROLOGY...
There are no hydrologic concerns through the first half of next
weekend.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --CT...None.
NY...None.
NJ...None.
MARINE...None.-- End Changed Discussion --

&&

$$

SYNOPSIS...JE/DS
NEAR TERM...JM/DS
SHORT TERM...DS
LONG TERM...JE
AVIATION...JE/BG
MARINE...JE/JM/DS
HYDROLOGY...JE/DS