okx-afd on 2025-01-12

628
FXUS61 KOKX 121915
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
215 PM EST Sun Jan 12 2025

.SYNOPSIS...
-- Changed Discussion --High pressure high pressure will gradually weaken and shift
more south of the region tonight. A wave of low pressure
approaches from SE Canada Monday into Monday night. A cold
front will pass across the area Monday night followed by high
pressure slowly building from the west through the end of the
week. A complex frontal boundary will work through next
weekend.-- End Changed Discussion --

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --Some slight adjustments with temperatures this afternoon.
Otherwise, the forecast remains on track.

Jet stream, South Central US through Northeast US, jet winds
increase through tonight.

For tonight a weak pressure gradient remains as high pressure axis
moves in and center of high pressure shifts south of the area. The
center of the high will be moving towards the Southeast US coast.

With mid level ridge axis moving east of the region, more trough
pattern takes shape. This will lead to decreasing subsidence. Mid
level low will be approaching from South Central Canada.

Would expect to have increasing and abundance of mid and high level
clouds coming over the ridge. While surface light winds will promote
more radiational cooling, the extra cloud coverage will
partially mitigate this.

Going to have a blend of NBM and MOS consensus for the area low
temperatures. This will make for a less vast range of lows and keep
temperatures slightly warmer for rural and outlying locations. Dry
conditions expected to prevail.-- End Changed Discussion --

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
-- Changed Discussion --Jet streak translates close to the region, staying just south of the
area Monday through Monday night.

Mid level zonal flow expected Monday through Monday night with the
mid level low moving from near northern Minnesota to the eastern
Great Lakes.

At the surface, low pressure travels eastward just north of the
Great Lakes. The low eventually gets to Southern Quebec to near
Maine by early Tuesday. An associated cold front moves across
the local area Monday night.

High pressure strengthens to the west of the low. The local
region will have a strengthening pressure gradient between the
low and high. A gusty WNW to NW flow develops as a result Monday
afternoon into Monday night.

Clouds will increase Monday into Monday night but decrease
later Monday night into Tuesday with surface high pressure
gradually building in. However, the center of the high pressure
stays well to the south and west of the region.

Used a blend of MAV and MET MOS guidance and added an extra
degree for the high temperature forecast on Monday. Increasing
WSW flow Monday and higher vertical mixing should allow for a
relatively warmer day than the previous day.

For lows Monday night, took a blend of NBM, consensus of raw
model data, as well as the MAV and MET MOS. While winds staying
up in the boundary layer and some extra clouds may be limiting
factors, there is still strong cold air advection indicated by
the models. The net result are lows about the same as the
previous night but wind chills will be much more apparent here.

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.-- End Changed Discussion --

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

* Dry, brisk, and cold 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
30-35 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 /19Z SUNDAY THROUGH FRIDAY/...
VFR as high pressure over the area through tonight slides east
on Mon.

Mainly NW winds at or just under 10 kt at most terminals should
back more to the W and diminish tonight, then become SW late
tonight. SW winds then increase to around or just under 10 kt
after 14Z Mon.

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

No unscheduled AMD expected.

OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY...

Monday afternoon: VFR. SW winds G20kt.

Monday night: VFR. Cold fropa early followed by W-NW winds
G15-20kt.

Tuesday through Wednesday: VFR. NW winds 15G25kt.

Wednesday night: VFR. NW winds G20kt in the evening.

Thursday: VFR.

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

.MARINE...
Conditions will remain below SCA levels through 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
daytime Tue into Tue night, but if the flow ends up stronger
than expected, gales could become more likely especially at
night.

SCA cond should carry through the day Wednesday and possibly
into the evening. A period of gales are possible on the ocean on
Wed. Cond should then settle down to sub-advisory levels by
early Thu morning.

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

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

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