000
FXUS61 KOKX 261034
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
634 AM EDT Wed Apr 26 2023
.SYNOPSIS...
High pressure over the region moves off the northeast coast today.
A weak area of low pressure moves across the region tonight into
Thursday morning. High pressure builds into the area behind the
low, and remains Thursday night. High pressure exits offshore
on Friday as a frontal system approaches from the west, moving
through the region Saturday. A second area of low pressure
develops in the Southeast this weekend, impacting the region
into early next week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
Wave of low pressure was approaching more quickly than
expected, and updated probabilities and sky cover to reflect
current conditions.
Temperatures have fallen into the lower and mid 30s, and even
to below freezing in a couple of location, and the frost
advisory remains in effect until 900 AM for portions of interior
southwestern Connecticut, the Lower Hudson Valley, and portions
of northeastern New Jersey.
Upper low pressure remains centered north of the Great Lakes
today and sends a weak shortwave across the region today. At the
surface a weak trough or area of low pressure across central
and western Pennsylvania was producing light rain showers. As
this low moves slowly eastward the chances of showers increases
from west to east. High pressure moving off the northeast coast
will slow the progression of the low. Thunder is not expected
with little to no instability, and minimal CAPE.
With increasing cloud cover, and a southeasterly flow
temperatures will be a few degrees below normal.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
The evolving upper low north of the Great Lakes region remains
tonight into Thursday and becomes a negative open trough. The
surface trough/low continues to track slowly east tonight into
Thursday, moving east of the region late Thursday as an upper
ridge and surface high build into the region. The chance for
showers will remain tonight into Thursday, with no thunder as
instability and CAPE remain minimal. With clearing expected
Thursday high temperatures will be near seasonal normals. The
high moves off to the northeast Thursday night as low pressure
begins to approach to the southwest.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
An active spring pattern sets up in the long term period, with
multiple rounds of rain expected.
The front half of Friday remains dry, with weak high pressure
retreating to the northeast as a mid-level shortwave and surface
low approach from the south and west. Increasing cloud cover in
the afternoon should give way to scattered rain showers by
evening, which likely continues overnight into much of Saturday
as a weak frontal wave develops along the coast.
Meanwhile, a more potent disturbance dives south across the
Central US. Ensembles continue to signal a deepening area of low
pressure along the East Coast Sunday into Monday as the trough
becomes negatively tilted.
Conditions may dry briefly Sunday as the one system departs and
the second is a bit slow to approach. Global models continue to
bounce around though with specific solutions, and Sunday
afternoon may end up predominantly dry before the intensifying
low arrives late Sunday into Monday. Capped PoPs at chance (50%)
Sunday afternoon given this trend. A strong jet oriented
overhead will aid divergence aloft and the potential for heavy
rain, and an increasing LLJ will enhance the potential for some
gusty winds, especially on Monday.
NBM probabilities for 2" or greater of rainfall from the system
have nudged up slightly compared to yesterday`s cycles, with a
widespread 25-50% likelihood. This instills a bit more
confidence of a higher QPF event than we`ve seen recently. WPC
added a marginal risk for excessive rainfall on Days 4-5
(Sun/Mon), which seems reasonable at this point. The storm
itself exits by Tuesday, though the upper low lingers nearby
into the middle of next week, maintaining the chance for showers
and cloud cover.
The persistent onshore flow and wet weather will keep
temperatures through the period below normals for the time of
year. Other than previously noted, national blended guidance was
followed with subtle adjustments.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
High pressure shifts offshore this morning, giving way to a
weak area of low pressure that moves across the region tonight.
VFR through the afternoon, gradually lowering cigs give way to
MVFR conds tonight with scattered rain showers. Brief IFR
possible after 6z Thu.
Mainly light and variable winds into the morning, becoming NE
at NYC terminals toward 12z, then turn SE by mid-to-late morning
and thereafter into the afternoon and evening. Speeds around 10
kt or less.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Wind shifts may be off by an hour or two.
Timing of MVFR may be off by several hours. Isolated shower possible
prior to introduction of PROB30 at 22z.
IFR cond possible, especially after 6z Thu.
OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...
Late Tonight: MVFR or lower in showers.
Thursday: MVFR/IFR in the morning as showers taper. Slight chance of
a shower east of NYC terminals in the afternoon.
Friday-Friday Night: VFR during the day, then MVFR or lower possible
in increasing chance of showers at night. E wind gusts 15-20 kt at
night.
Saturday: MVFR or lower in rain. E wind gusts 20-25 kt.
Sunday: MVFR or lower in rain. E to SE winds 15-20 kt gusting 25-30
kt.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
-- Changed Discussion --
Only minor changes made to the winds to reflect current
conditions. Also updated weather as showers were approaching
from the west.
Winds and seas remain below small craft advisory levels through
Friday with high pressure over the waters today, and a weak
area of low pressure that passe through the waters tonight into
Thursday. High pressure then returns Thursday night and moves
northeast Friday.
Low pressure passing through the waters late Friday into
Saturday will lead to an increasing easterly flow.
SCA conds return this weekend as ocean seas build to 5 ft by
early Saturday morning, and remain elevated into early next
week. E gusts 25-30 kt develop on most waters on Saturday,
potentially continuing through the remainder of the weekend as
another area of low pressure approaches and moves through into
early next week.
A period of gales is possible, especially on the ocean, Sunday
into Monday.-- End Changed Discussion --
&&
.HYDROLOGY...
No hydrologic impacts are expected with showers today into
Thursday.
A series of systems impact the region late Friday into early
next week, bringing several rounds of rain that may fall locally
heavy rain at times.
Hydrologic impacts are possible, with minor flooding in urban, poor
drainage, and low-lying areas the most likely solution at this time.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Frost Advisory until 9 AM EDT this morning for CTZ005-006.
NY...Frost Advisory until 9 AM EDT this morning for NYZ067>070.
NJ...Frost Advisory until 9 AM EDT this morning for NJZ002-103.
MARINE...None.
&&
$$
SYNOPSIS...DR/MET
NEAR TERM...MET
SHORT TERM...MET
LONG TERM...DR
AVIATION...DR
MARINE...DR/MET
HYDROLOGY...DR/MET