000
FXUS61 KOKX 240612
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
212 AM EDT Wed Apr 24 2024

.SYNOPSIS...
A frontal system approaches overnight and moves across the area
on Wednesday. Strong high pressure then builds in Wednesday night
through the end of the week. The high centered over the region on
Friday gradually shifts offshore into Saturday then pushes farther
south on Sunday as a low from the western Great Lakes moves into
Canada. This low brings a warm front Saturday night into Sunday.
We remain between low pressure to the north and high pressure to
the south through early next week.

&&

.NEAR TERM /THROUGH TODAY/...
Weakening high pressure offshore continues to give way to an
approaching frontal system. Mid and high level moisture
increases overnight along with a southerly flow ahead of the
system. Most of the night will be dry with a few showers
possible in the early morning as the associated warm front moves
through the area. Moisture and lift are limited and any of the
showers look light. In fact, most CAMs show the activity
diminishing as it moves eastward, likely due to dry low levels.
Low temperatures tonight will not be as cold as recent nights
with lows in the 40s across the region.

Behind the warm front, a WNW-WSW flow develops late morning
into the afternoon. The trailing cold front will quickly sweep
across the area from NW to SE middle to late afternoon. Forecast
soundings are continuing to show some surface instability.
However, there are still hints of middle level capping along
with dry sub cloud. For these reasons, have continued to leave
thunder out of the forecast. Some isolated low topped convection
may still develop in the afternoon and could contain gusty
winds with the inverted V soundings/dry subcloud air. Dew points
should start mixing out in the afternoon, but a more
substantial drop in dew points is likely late in the afternoon
and evening. The westerly component and deep mixing should allow
temperatures to rise into the 60s across the entire area. Wind
gusts 25-30 mph are possible late in the day. Temperatures could
end up around 70 degrees in the NYC metro and urban NE NJ.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
Any lingering showers end by sunset with skies quickly becoming
clear. The main story for Wednesday night will be the much
colder air that settles over the region in response to a strong
high pressure building in from southeast Canada. Temperatures
are likely to fall into the upper 20s and lower 30s across the
interior and middle to upper 30s most elsewhere. Lows in the NYC
metro should fall close to 40 degrees. Winds will likely remain
up through the night although there is a short window early
Thursday morning just before sunrise for winds to lighten across
the interior. These areas have a higher probability for seeing
temperatures fall below freezing. Have issued a Freeze Watch for
interior S CT, Lower Hudson Valley, and W Passaic and W Bergen
from 3am through 9am Thursday. Frost will not occur due to the
dry air (dew points falling into the teens and low 20s).

Strong high pressure will then dominate the weather Thursday into
Thursday night. The center of the high settles overhead on Thursday
with winds becoming light. An unseasonably cool air mass in place
will lead to below normal temperatures in the 50s. Frost and freeze
conditions appear likely again Thursday night into Friday morning
with coldest readings inland. Modification of the air mass should
lead to more low level moisture and potential frost development.
Additional frost/freeze headlines may be needed. Lows range from the
low 30s inland to the middle and upper 30s near the coast.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
An Omega blocking pattern becomes established on Friday, as a
deep trough remains across eastern Canada into the northern
Atlantic, with another trough through the Rocky Mountain region
into the Plains, and a high amplitude ridge in between. As a
result, systems will be slow to move eastward into the beginning
of next week. And a northern Plains low will be slow to move
into the ridge Sunday into Monday.

With surface high pressure over the region moving offshore Saturday,
there is a lot of uncertainty with the development and movement of a
warm front Saturday night into Sunday, as ridging remains. This warm
from will be coming from a low in the western Great Lakes as it
moves into Canada to our north. Some isolated to spotty showers
could for along the warm front boundary Saturday evening into early
Sunday morning.

A deep return flow sets up for late in the upcoming weekend and
temperatures initially below normal through Saturday quickly rise to
as much as 10-15 degrees above normal Saturday night into the
beginning of next week. The warmest day looks to be Monday with the
western interior and the NYC metro warming into the low-80s, while
the rest of the region will be in the upper-to-mid 70s. Used the NBM
guidance through the extended period with the exception of POPs. A
weak low will attempt to bring more slight chance POPs to the area
on Tuesday with a cold front. Frost headlines look less likely
Friday night with the exception of the far interior.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
A frontal system will approach overnight and move across today.
Strong high pressure will then build in tonight.

The frontal system will mainly come through the area dry with a
low chance of showers, possibly even a thunderstorm Wednesday
afternoon. Any associated MVFR conditions will be short lived,
with the best chance this morning.

Southerly winds overnight will generally decrease to 10 kt or
less. Winds then veer to the SW with the passage of the warm
front mid to late this morning, becoming WNW by afternoon behind
the cold front. G15-20kt will develop in the morning, then
G20-25kt in the afternoon. Winds then veer N and diminish
somewhat late this evening.

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

Timing of wind shifts with multiple frontal boundaries may vary
by 1-2 hours, especially with the shift to WNW.

There is low chance of a thunderstorm along the cold front this
afternoon.

OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...

Late tonight: VFR with diminishing N winds.

Thursday and Friday: VFR.

Saturday and Sunday: Mainly VFR. Low chance of MVFR in showers.

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

&&

.MARINE...
Wind gusts across the lower New York Harbor have diminished to
below 25 kt, and the advisory was allowed to expire.

Strengthening S flow continues overnight. SCA conditions expand
eastward across the ocean overnight into Wednesday. Winds will
start weakening Wednesday night and especially Thursday, but
ocean seas will remain elevated. The SCA remains in effect on
the ocean through Wednesday night, but may need to be extended
into Thursday.

A weakening pressure gradient will otherwise lead to conditions
below SCA levels through the end of the week. High pressure
remains in control Saturday, moving offshore Saturday night,
with conditions below SCA levels through the weekend.

&&

.FIRE WEATHER...
RH will be higher for the first half of Wednesday, but
increasing W winds in the afternoon will lead to falling RH
values. A wetting rainfall is not expected. Elevated fire spread
conditions may present themselves for NE NJ in the later parts
of the afternoon/early evening as gusts 25-30 mph occur and RH
values fall into the lower to middle 30s.

Min RH values will be in the lower 20s on Thursday, but winds
will be light and largely under 10 mph.

&&

.HYDROLOGY...
No hydrologic concerns through early next week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Freeze Watch from late tonight through Thursday morning for
     CTZ005>008.
NY...Freeze Watch from late tonight through Thursday morning for
     NYZ067>070.
NJ...Freeze Watch from late tonight through Thursday morning for
     NJZ002-103.
MARINE...Small Craft Advisory until 6 AM EDT Thursday for ANZ350.
     Small Craft Advisory until 6 AM EDT Thursday for ANZ353-355.

&&

$$

SYNOPSIS...BR/DS/DW
NEAR TERM...BR/DS/MET/DW
SHORT TERM...DS
LONG TERM...BR
AVIATION...BG/DW
MARINE...BR/DS/MET
FIRE WEATHER...
HYDROLOGY...BR/DS

NWS OKX Office Area Forecast Discussion