000
FXUS61 KOKX 231134
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
634 AM EST Tue Jan 23 2024
.SYNOPSIS...
A weak frontal system will pass through the region today and
tonight, then move north of the area on Wednesday, with another
disturbance following behind it Thursday into Friday. An area of low
pressure develops over the Deep South into the weekend, likely
tracking near the region early next week.
&&
.NEAR TERM /THROUGH TONIGHT/...
*Winter Weather Advisory across portion of the interior from
12pm today until 10am Wed *
Forecast update to reflect current conditions, otherwise no
changes. A frontal boundary north of the region, will gradually
move closer to the area today. Light precipitation is expect to
develop from about mid morning onward as a shortwave approaches
from the west. Stuck fairly close to the latest 00z hi-res
guidance (NAM 3K, FV3, WRF ARW) which were fairly consistent
with much of the precipitation today remaining across the
interior. Temperatures aloft start off somewhat mild, however
temperatures at the surface will be right at or slightly above
the freezing mark. This will make for a tricky p-type forecast.
As temperatures wet bulb with the onset of precipitation, am
thinking that there will be a decent chance of freezing rain
across portions of the interior (Lower Hudson Valley, interior S
CT, Western Passaic). Closer to the coast, if any precipitation
develops, it should be warm enough for just plain rain. Can not
rule out some sleet as well across the interior. With
confidence growing for freezing rain to develop today across the
interior, have decided to go with winter weather advisories for
the threat of ice. Note: only a trace of freezing rain is
required for winter weather advisory.
The frontal boundary north of the region approaches through the
afternoon as a backdoor cold front as high pressure moves across
Quebec. As the front sags southward into the region, temperatures
aloft will cool from NE to SW on a northerly flow. As a result,
expect the rain/freezing rain to transition to a wintry mix (more
snow than sleet/freezing rain) around sunset. The wintry mix should
make it down through the Lower Hudson Valley/interior NJ and to the
CT coast. Bufkit soundings showing that NYC Metro/Long Island
should remain rain for most if not all of the period.
Between 06-09z, Temps aloft then start to rise again, so where we
have that snow/wintry mix occurring, a transition to an icy mix
or fzra is again likely.
The lift is not particularly strong with this event, so mainly light
pcpn is expected throughout. This should keep any snowfall accums
less than an inch with the rates too low. The main hazard will be
where the pockets of -fzra develop, leading to icy spots.
highs today will be in the 30s, with lower across the interior and
upper 30s closer to the coast. Tonight temperatures fall into the
lower and middle 30s.
&&
.SHORT TERM /WEDNESDAY/...
By Wednesday morning the frontal boundary starts to lift north
again. We are expecting temperatures both aloft and at the surface
to rise, resulting in any frozen precipitation to change over to
plain rain by about mid morning. Will keep the Winter weather
advisory in effect through the Wed morning rush hour commute with
hazardous conditions expected from the overnight wintry
precipitation. POPs remain rather light Wednesday morning as
the first wave of precipitation lifts north. POPs increase once
again late Wednesday afternoon as another wave approaches. This
second wave is expected to be just plain rain.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
*Key Points*
* Gradual warming trend into late week, temperatures 10 to 15
degrees above normal by Friday.
* Multiple rounds of precipitation with several waves of low
pressure impacting the region through the weekend.
Region remains on the northern periphery of broad ridging over the
Eastern US to start the period. Frontal boundary meanders near the
region on Wednesday night, gradually lifting back north by Thursday
as weak low pressure exits the New England coast. Low pressure is
progged to pass to our north and drag a cold front through the area
Thursday night into Friday morning, with periods of rain through
then.
A brief reprieve then looks likely thru Saturday with zonal flow and
weak high pressure temporarily in place. Global guidance is in
fairly good agreement in another shortwave spurring low pressure
development over the Deep South by Saturday, eventually emerging off
the Mid Atlantic coast toward the latter half of the weekend. While
confidence is low at this stage, it`s not out of the question that
ptypes could become a factor with this system locally should
Canadian high pressure build in quick enough to allow a marginally
cold enough air mass to support it.
Despite the multiple periods of precipitation, the extended does not
necessarily look like a washout. Ensemble means prog total
precipitation thru early next week at or under 2 inches, which
occurring over several days, should help to preclude any significant
hydro concerns. In addition, the moderating flow on the backside of
the high helps to thaw out the region from the recent cold spell. A
gradual warming trend looks to peak Friday, when forecast highs are
progged in the 50s, or upwards of 15 degrees above normal for late
January.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
A weak cold front sags south, meeting up with warm front from
the southwest and creating a nearly stationary front over the
region tonight into Wednesday.
VFR prevails for the the city terminals today before lowering to
MVFR late tonight. Rain showers will be possible here for a few
hours this afternoon and again late tonight. Elsewhere, MVFR and
even IFR arrives earlier - starting this afternoon in most spots. A
wintry mix begins this afternoon as well, with the exception of
KISP, which probably remains dry, but may see some afternoon rain
showers.
SW-W winds around 10kt or less veer more northerly and weaken
this afternoon, becoming light and variable late in the day,
then shifting easterly late tonight.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Should rain occur this afternoon and night, there is a chance that
it could mix with sleet. Low confidence in this regard. Tempo MVFR
cigs/vsbys possible from approx 17-20z. Chance of IFR after 06z.
OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY...
Wednesday-Thursday Night...MVFR/IFR. Periods of rain mostly from
Wednesday night through Thursday night.
Friday...Chance of MVFR/IFR/rain AM. Chance of improvement to VFR in
the afternoon.
Saturday...Mainly VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Winds and seas continue to diminish on the area waters with just
small crafts left up on the eastern ocean zone from Moriches Inlet
to Montauk Point until 10am. Expect some leftover gusts to 25kt
and seas around 5 ft. Conditions are expected to fall below SCA
criteria by mid morning with sub-SCA conditions expected
through at least Thursday and perhaps into the weekend with a
weak pressure gradient in place.
&&
.HYDROLOGY...
No hydrologic impacts are expected through the weekend.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Winter Weather Advisory from noon today to 10 AM EST Wednesday
for CTZ005-006.
NY...Winter Weather Advisory from noon today to 10 AM EST Wednesday
for NYZ067>070.
NJ...Winter Weather Advisory from noon today to 10 AM EST Wednesday
for NJZ002-103.
MARINE...Small Craft Advisory until 10 AM EST this morning for ANZ350.
&&
$$
SYNOPSIS...BC/DR
NEAR TERM...BC
SHORT TERM...BC
LONG TERM...BC/DR
AVIATION...JC
MARINE...BC/DR
HYDROLOGY...BC/DR