000
FXUS61 KOKX 042201
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
601 PM EDT Tue Apr 4 2023
.SYNOPSIS...
A backdoor cold front moves into the area tonight and remains
in the vicinity through Wednesday. The front returns north as a
warm front Wednesday night. A cold front approaches Thursday,
moving through the region Thursday evening. High pressure will
then build in from the Great Lakes through the weekend, sliding
offshore by early next week.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
-- Changed Discussion --
The moist southerly flow has allowed a low stratus deck to
develop and drift north over much of Long Island and coastal
Connecticut, while a weak quasi-stationary boundary lies just to
the north of this, extending from along the New York/Pennsylvania
border eastward into the lower Hudson Valley and then across
southern Massachusetts. Only subtle changes made with this
evening update and previous discussion follows.
With a colder airmass to the north, and with high pressure
building southward through tonight this front will be pushed
southward as a backdoor cold front. With the flow shifting to
the north and northeast, the front will come through the the
northern and eastern sections and then push farther to the south
and west late tonight and likely be through the area by
Wednesday morning. There will be little forcing with the
boundary, and moisture will be shallow, with stratus developing.
Right along the front there will be some better lift, and while
much of the precipitation will be drizzle, along the front will
have a slight chance of rain. Fog is not expected to develop
until late tonight as the winds shift to the east and surface
dew points begin to increase. There is some uncertainty with the
overnight low temperatures, and will be dependent on how far
west and south the front moves through the overnight hours.-- End Changed Discussion --
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
The front does become stationary somewhere in the vicinity. With
a cool airmass and an easterly flow continuing as the high
moves off the New England coast during the day, there will be
weak cooler air damming as a more south to southeast flow
remains to the west and south. With the front in the vicinity
and shallow moisture in place will continue with the chance of
drizzle and fog.
As low pressure moves into southern Canada with a cold front
approaching to the west late Wednesday night, the flow across
the area will eventually shift to the south and the weak stalled
boundary will either dissipate or move to the north as a warm
front, however the best warm front formation will be well to the
north late Wednesday night into Thursday morning. Will
maintain a chance of drizzle, however, this may be overdone as
the area may become warm sectored late at night with a dry
period possible before showers move into the area with the cold
front.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
The period begins with the warmest day of the year so far for
parts of the region. As an upper ridge axis slides offshore on
Thursday, troughing over the Northern Plains begins to push
east. This will lift a warm front north through the region early
Thu morning, with increasing southwesterly flow. An attendant
cold front approaches from the west late in the day, with the
potential for convective development along and ahead of this
boundary.
After some lingering low clouds associated with the nearby warm
front early in the day, expect a quick jump in temperatures as
the BL mixes. Areas west of the Hudson River and away from the
maritime influence of the cooler waters, expect temperatures to
climb into the 70s, with isolated lower 80s possible in parts of
urban NE NJ, or around 20 degrees above normal. It`s possible
KEWR`s daily record high of 80 degrees could be challenged.
Across Long Island and Southern Connecticut, the SW wind off the
waters will hold temperatures down in the 60s, and even upper
50s along the immediate shoreline.
Given the warm, moist air mass inland, there will be some
amount of instability ahead of the front, with BUFKIT soundings
indicating SBCAPE values of several hundred joules possible. SPC
has a general thunder risk outlined for the entire area, with a
marginal straddling parts of interior NE NJ and Orange County
NY. Bulk shear 0-6 km values are progged between 40 and 60 kt,
and ample moisture will be present as PWATs climb to over 1.5
in, or about as high as observed this time of year. Timing looks
to be primarily in the afternoon and early evening, with the
front itself following shortly thereafter into the evening.
Fortunately, the flow looks pretty progressive, so not too
concerned with hydrological issues from this system, though a
quick quarter to half inch is possible. The primary threat from
any strong to severe thunderstorm would be damaging wind gusts.
Conditions dry out from west to east Thursday evening behind
the front, with winds veering northwest, helping to advect in
drier, cooler air to end the work week. Friday through the
weekend will be dry as a 1035 mb surface high pressure builds in
from the Great Lakes. Gusty NW winds 25 to 30 mph are possible
on Friday as the high builds in, but then lower over the
weekend. With the northwest flow, temperatures will be cooler
during this time, generally 50s and lower 60s, with increasing
sun through Sunday.
The evolution of the large scale pattern becomes more uncertain to
start next week. The latest model consensus has the surface high
starting to move offshore, but lingering ridging may hold on during
Monday. There may be an approaching upper trough, but the timing and
amplitude continue to have little consistency. Generally stuck close
to national blended guidance for this update.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
A stationary front remains through the region this evening and
then sags south of the terminals tonight as a cold front.
Mainly VFR through 00z. Conditions will then lower tonight,
becoming IFR and LIFR late tonight/early Wednesday morning.
Drizzle or sprinkles are possible mainly late tonight/early
Wednesday morning.
SE to S winds around 10 kt or less. Winds become E-NE after
around midnight as the cold front sags southward. Winds then
increase 10-15 kt on Wednesday.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Chance that winds veer S at KEWR for a period late this
afternoon into early evening. Wind shift to ENE may be off by
1-2 hours, otherwise moderate to high confidence in wind
forecast. Moderate confidence in cigs tonight. Low to moderate
confidence in vsbys. Drizzle might not occur tonight.
...OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
Wednesday PM: MVFR/IFR with a chance of light rain or drizzle.
E gusts 15-20 kt possible.
Wednesday Night-Thursday Night: MVFR/IFR Wednesday night into
Thursday morning. MVFR-VFR Thursday afternoon and night. Chance
of showers with a slight chance of a thunderstorms Wednesday
night, showers likely with a chance thunderstorms Thursday
afternoon and evening. SW gusts 15-20kt, becoming W-NW Thursday
night. LLWS possible late Wednesday night.
Friday-Sunday: VFR. W-NW G20-25kt Friday morning.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90.-- End Changed Discussion --
&&
.MARINE...
With a relatively weak pressure gradient in place through
Wednesday evening winds and seas will remain below SCA levels
across the forecast waters tonight into Wednesday evening.
Southerly winds may be increasing late Wednesday night,
especially across the western waters as a low pressure
approaches to the west and a warm front lifts to the north. Will
be toward morning before gusts and possibly ocean seas near SCA
levels on the western waters. Being late in the 3rd period will
hold off on issuing an advisory.
Increasing SW flow on Thursday brings SCA conds to the ocean,
with gusts around 25 kt and seas 4 to 6 ft into Thursday
evening. Non- ocean waters are forecast to remain below SCA
Thursday and Thursday night.
SCA conditions are then possible on all waters Friday as high
pressure builds in, potentially bringing NW gusts around 25 kt,
before lowering Friday night. Sub-SCA conditions are expected on
all waters through the weekend with high pressure in control.
&&
.HYDROLOGY...
No hydrologic concerns are expected through early next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...DR/MET
NEAR TERM...DR/MET
SHORT TERM...MET
LONG TERM...DR
AVIATION...JC
MARINE...DR/MET
HYDROLOGY...DR/MET