000
FXUS61 KOKX 171727
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1227 PM EST Wed Jan 17 2024
.SYNOPSIS...
High pressure builds in from the south and west today before
sliding offshore Thursday. Low pressure develops off the Carolina
coast Thursday night, passing east of the area Friday. High
pressure then builds south of the region through the beginning of
next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Forecast remains on track with only minor adjustments to
account for the latest observations in temperature and dew
point. With frigid temperatures, there still remains the
potential for patchy ice on untreated surfaces, especially if
the surfaces are in the shade.
Otherwise, flow aloft transitions to more zonal as surface high
pressure builds in from the south and west. Remaining very cold
this afternoon, 850 mb temps progged below -15C, and surface
temperatures should remain in the 20s for the bulk of the
region, the coldest day since last February for some. Factoring
in a blustery NW wind with a tightened pressure gradient, wind
chills likely sit in the teens this afternoon.
High pressure continues to build in tonight but its center
remains far removed from the local area. Lows tonight once
again fall into the teens and lower 20s.-- End Changed Discussion --
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
High pressure slides offshore early Thursday and heights briefly
rise aloft. Thursday features decreasing winds, increasing cloud
cover, and cold conditions. Can`t rule out a few flurries or
snow showers across the northern tier as a weak disturbance
passes by. Coastal areas tops out around the freezing mark in
the afternoon, with upper 20s inland.
Attention then turns to a developing coastal low that looks to
bring a light snowfall to the area Friday into Friday night.
Shortwave energy rounding the base of an incoming upper trough
will help spur cyclogenesis off the East Coast, skirting the
region as it passes east. Ensemble means prog the trough to
remain positively titled, which would allow a more progressive
flow to scoot the low farther out to sea relatively quickly.
Still some uncertainty as to how quickly this occurs, especially
if the low attempts to deepen quicker than currently modeled,
or if the trough ends up a bit more amplified. Regardless, a
period of light snow is likely to fall once again across the
region on Friday. Unlike recent events, profiles support all
snow down to the coast, with surface temperatures in the 20s and
lower 30s, and sufficient deep layered cold air aloft.
Snow looks to develop into early Friday morning from the south,
continuing to fall lightly much of the day before tapering by
the early evening. The PM commute on Friday is likely to be
impacted by falling snow and reduced visibility. QPF will be
light, generally under a quarter inch total, and thus,
accumulations are expected to be light, on the order of a couple
inches. The 01Z NBM came in with roughly 50% of members producing
2" across NE NJ, NYC, and Long Island, lowering to 25% for the
Lower Hudson Valley and southern CT. This tracks closely with
updated totals, a widespread 1 to 3 inches, highest amounts
across the southern half of the CWA.
While a relatively minor event, whether by snowfall or travel
impacts to the Friday evening commute, a Winter Weather Advisory
may eventually be needed for portions of the area.
Conditions begin to dry Fri night as the low continues exiting well
offshore, setting the stage for a sprawling arctic high to gradually
build in its wake this weekend.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
A 1040s high centered over the middle of the country on Sat builds
S of the area thru Tue. It will be cold over the weekend with
temps blw average. NW winds will keep wind chills in the single
digits and teens on Sat, with wind chills dropping blw zero Sat
ngt in some of the outlying areas. Temps aloft warm a bit on
Sun, so slightly warmer but highs still likely aob freezing. The
NBM was followed.
Heights rise Mon and Tue with a further warming trend. By Tue,
projected highs are abv normal. Some rain is possible on Tue as
GOMEX moisture begins to feed nwd into the region. This setup could
produce some spotty fzra at times across the interior before the
airmass warms sufficiently from the top down. The NBM was
followed.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
-- Changed Discussion --
VFR as high pressure builds in through tonight and then shifts
offshore on Thursday.
W winds generally 15 kt with gusts around 25 kt will continue
through this evening. Sustained winds and gusts will diminish this
evening into the overnight, likely occurring first at outlying
terminals. W-WSW winds may then weaken below 10 kt briefly
towards day break Thursday before increasing to around 10 kt
late Thursday morning and afternoon. The wind direction should
also back to the SW on Thursday.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Gusts may end 1-3 hours sooner than in TAF tonight.
OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY...
Thursday Afternoon-Night: VFR.
Friday...IFR with snow becoming likely in the morning and
afternoon, continuing into the early evening. NE-N wind gusts
20 kt in the afternoon and at night.
Saturday-Sunday...Mainly VFR. N-NW wind gusts 25-30 kt Saturday and
20-25 kt on Sunday.
Monday...VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Small Craft Advisory is now in effect on all waters thru 6 am
Thu. While winds may be marginal on the non ocean waters for a
period this morning, increasing NW flow should allow 25 kt gusts
to redevelop by afternoon. In addition, with the cold air and
gusty winds, chance for light freezing spray for the ocean
waters and eastern Long Island Sound today.
Winds lower Thursday with sub SCA conditions returning to non
ocean waters early in the day, and on the ocean by Thursday
night due to lingering 5 ft seas.
SCA conditions redevelop late Friday on at least the ocean with
25-30 kt gusts likely. This may persist on the ocean over the
weekend on mrgnl nwly winds and seas around 5 ft. Winds and seas
may be blw SCA lvls for all waters on Mon.
&&
.HYDROLOGY...
No hydrologic impacts are expected through the forecast period.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EST Thursday for ANZ331-332-
335-338-340-345-350-353-355.
&&
$$
SYNOPSIS...JMC/DR
NEAR TERM...DR/MW
SHORT TERM...DR
LONG TERM...JMC
AVIATION...DS
MARINE...JMC/DR
HYDROLOGY...JMC/DR