789
FXUS61 KOKX 271129
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
629 AM EST Wed Nov 27 2024
.SYNOPSIS...
-- Changed Discussion --
High pressure builds south of the region today, followed by low
pressure passing over or just south of the area on
Thanksgiving. Polar high pressure over the Northern Plains
builds southeast into the Mississippi and Tennessee Valleys
Friday and through the weekend. The high then remains over the
the southeastern states Monday and Tuesday. Meanwhile low
pressure remains to the north of the region.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A 1021 high was centered over WV this mrng. Zonal flow aloft
will keep the high S of the region and low pres spinning near
James Bay. Resultant flow is a wly breeze around 10-15 mph at
times. Temps close to normal per the NBM. Water vapor shows the
subtropical Pacific tap, so increasing high clouds can be
expected, particularly in the aftn.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
Models clustering on a low pres soln passing just S of or over
LI on Thanksgiving. Based on the consensus timing, expect pcpn
to develop most areas before sunrise. Across the interior,
especially nwrn Orange county, at least a mix of rain and snow
is expected at the onset until the waa warms the column
sufficiently. A mdt burst of snow can often occur in this
scenario before the complete changeover. As a result, the fcst
includes around an inch of snow for the mrng hours across Orange
county, especially out near Port Jervis. Worst case attm, minus
a significant change in track, would be around 3 inches nwrn
Orange county with around an inch Putnam to nrn Passaic.
Elsewhere, a cold rain just about all day.
Went with the 00Z NAMDNG 2m temps blended with 20% NBM for high
temps on Thanksgiving, bringing the warm sector into LI and
keeping the colder air trapped across the interior.
The low may track right over the area, particularly srn areas,
which would result in a lull in winds as it does. There could
also be a brief period of fog/dz with the low passage. With the
low only progged to get into the high 990s invof the cwa, winds
otherwise should max out around 30 mph, strongest late in the
day into the eve as the low exits.
The low is modeled to exit quickly Thu ngt with the dry slot
surging thru, reducing chances for any meaningful transition
back to snow attm.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
Key Point:
* Prolonged period of dry and seasonably cold conditions through the
extended period
A continental polar airmass will dominate the weather throughout the
extended period, as high pressure moves through the Northern Plains
and into the southeastern states through the period.
Meanwhile low pressure remains across southeastern Canada, and a
surface through remains offshore of the mid Atlantic region. The
forecast remains very consistent with little to no changes.
Temperatures will be generally 5 to 10 degrees below seasonal
normals through the period, and a west to northwest flow will
dominate, becoming gusty at times during the day, especially Friday
and through the weekend. With blustery wind chills are likely to run
7 to 10 degrees colder than actual air temperatures at times.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
High pressure builds to the south this morning and shifts
offshore this afternoon. Low pressure will then approach toward
Thursday morning, passing across the region Thanksgiving
morning.
VFR through most of tonight, lowering to MVFR, possibly IFR,
toward daybreak with rain pushing in. Chance of a rain/snow mix
at KSWF early in the morning.
Winds generally west 5 to near 10kt through much of today
before backing more WSW-SW near sundown and becoming lighter.
Light and variable winds become east toward Thanksgiving
morning.
...NY Metro (KEWR/KLGA/KJFK/KTEB)TAF Uncertainty...
No unscheduled amendments expected until late tonight. After 09Z
amendments possible with lowering flight conditions on timing
of onset of rain.
OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
Thursday: Rain with IFR conditions likely, possibly a rain/snow
mix early at KSWF. E-NE winds G20kt in the afternoon, becoming
W/NW late in the day and at night.
Friday: VFR.
Saturday: VFR. W winds G20-25kt.
Sunday: VFR. W winds G15-20kt.
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 blw sca lvls today. Increasing winds late tngt
thru Thu as low pres tracks across the waters. A sca will likely
be needed Thu and Thu ngt.
Marginal small craft conditions will be possible on the ocean waters
Friday morning with a strong and gusty northwest flow.
Conditions will briefly be sub SCA Friday afternoon, and then
marginal conditions will once again be possible on the ocean waters
late Friday night into Saturday evening with a gusty west flow, with
the eastern ocean most likely to have SCA conditions.
Then from late Saturday night into the beginning of next week winds
and seas will remain be advisory levels on all the waters.
&&
.HYDROLOGY...
No hydrologic impacts are expected thru the beginning of next
week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JMC/MET
NEAR TERM...JMC
SHORT TERM...JMC
LONG TERM...MET
AVIATION...JC/MET
MARINE...JMC/MET
HYDROLOGY...JMC/MET