000
FXUS61 KOKX 210958
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
558 AM EDT Wed Jun 21 2023
.SYNOPSIS...
High pressure remains over New England today before shifting
east into the Atlantic on Thursday ahead of an incoming warm
front. A weak frontal system over the Ohio Valley and the Mid
Atlantic tracks slowly northward Friday and then remains in the
area through the weekend. Another, deeper, frontal system
approaches from the Great Lakes Monday with a cold front passing
through the area Tuesday.
&&
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Minor adjustments made to account for current observations, but
forecast remains on track.
Strong ridging over the Upper Midwest begins to build east
today, with a 1028 mb surface high remaining situated over
northern New England. Meanwhile, a cutoff low continues to
meander over the Southeast, with the local region sandwiched in
between these features.
Increasing cloud cover can be expected across coastal areas as a
frontal wave begins to track northward into the Mid Atlantic this
evening, though a dry day is expected. The high pressure both
aloft and the surface will create subsidence and prevent any
precipitation from making it this far north for the moment. Plenty
of high clouds can be expected though, coupled with some stratocu,
especially closer to the coast. Skies may end up partly to mostly
sunny inland as the moisture runs into the ridge. Clouds thicken
further tonight ahead of an approaching warm front, with showers
developing for southern areas by daybreak or so Thursday.
The easterly flow increases as the pressure gradient begins to
tighten. A modest 10-15 mph surface flow develops by the
afternoon, with gusts 20-25 mph. The strongest winds look to
occur closer to the coast where a few gusts up to 30 mph are
possible.
Highs will continue below normal for this time of year in the
low to mid 70s. Lows tonight will range from the lower 50s
inland, to around 60 in the urban metro.-- End Changed Discussion --
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
Surface high pressure shifts farther east into the Atlantic on
Thursday as a warm front lifts north toward the region.
Hi-res CAMs indicate a band of rain developing ahead of this and
eventually overspreading the region from south to north. The
departing high and ridging aloft will try to impede this however,
slowing its progression as the rain runs into a much drier and
more stable environment. Significant mid level dry air will
have to be overcome, which may take into the afternoon hours for
parts of the northern interior to saturate. While the rain is
expected to weaken, if not dissipate as it moves farther inland,
guidance indicates additional shortwave energy moving around
the cutoff low Thursday night, potentially bringing another
round of showers.
The 00z HREF paints a general 0.25" to 0.75" across NYC and Long
Island through Thursday night, with less than a quarter inch into
interior CT and the Lower Hudson Valley. Fortunately, rates do
not appear to rise to a level of concern, though some brief
minor flooding may be possible in any locally heavy downpours.
The rain and clouds will limit surface heating on Thursday, with
little diurnal variation in temperatures expected. Highs for most
top out in the upper 60s, about 10 to 15 degrees below normal, and
remain in the 60s overnight into Friday morning. With subtle
adjustments, followed a combination of national blended guidance
and the super blend for this update.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
The long term will continue to be characterized by a nearly blocked
pattern, atypical of mid-June for this part of the country, as an
upper ridge remains over the western Atlantic.
A cutoff low over the Southeast US will be opening into a longwave
trough Friday and then moves slowly through the region through
Sunday. Another upper rough moves out of Canada into the Great Lakes
region for the beginning of next week. Weak surface low pressure to
the south of the region Thursday will move into the area Friday and
remain into the weekend. Then another, deeper, surface low moves
slowly through the Great Lakes with a cold front moving through
Tuesday. A portion of northeastern New Jersey and the lower HUdson
Valley are in a marginal risk for excessive rainfall Friday and
Saturday with periods of moderate rainfall possible with warm cloud
processes dominating. However, there is uncertainty if flash flood
guidance will be exceeded as the NBM is indicating low chances for
rainfall rates exceeding 2 to 3 inches in 3 and 6 hours.
Temperatures Friday into the beginning of next week will be near
normal levels as a warm and humid airmass remains, with dew points
in the mid 60s, and at times near 70 across inland locations.
&&
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
High pressure remains to the north through today and drifts offshore
tonight as low pressure approaches from the south.
VFR. There is a chance of MVFR ceilings, mainly along the
Connecticut coast, and at KTEB and KHPN, with a lower chance at KISP
and KJFK. Areas of stratus has already developed along the
Connecticut coast and into northeastern New Jersey with periods of
MVFR ceilings at KBDR and KTEB.
Winds will be NE to E and increase in the morning with gusts
developing. There is some timing uncertainty with the onset of
gusts, and more uncertainty with the ending of gusts Wednesday
evening.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Uncertainty in how widespread MVFR stratus development will be early
this morning, with the chance that MVFR conditions occur at KJFK and
KLGA. More confidence of MVFR at KTEB, and included TEMPO MVFR into
early morning. Timing of gusts ending this evening may be earlier.
OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...
Late Wednesday night: VFR. Conditions likely lower to MVFR toward
morning, 09Z, along the coast as showers develop.
Thursday: Showers likely. MVFR, possibly IFR at times. E winds G15-
25 kt along the coast.
Friday through Sunday: Showers likely with MVFR or lower conds at
times. Tstms also possible, mainly afternoon into
evening.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Increasing easterly flow today will allow for gusts up to 25 kt
to develop on the ocean waters and the NY Harbor by the
afternoon. This will also build ocean seas to 5 to 6 ft through
the day. Winds everywhere should settle closer to 15 to 20 kt
by tonight, but gusts of 25 to 30 kt may return Thursday morning
on near-shore waters, including the NY Harbor, as well as the
ocean. An additional SCA may be needed for these waters. Winds
diminish by Thursday afternoon, but ocean seas will remain
elevated. Have extended the SCA on the ocean through 8 pm
Thursday due to this, and a further extension into Thursday night
may be needed.
Winds and seas are expected to remain below SCA levels Friday and
Saturday as weak low pressure remains in the vicinity. Ocean seas
may be near or over SCA levels Sunday into Monday evening with a
persistent southerly flow that increases Monday, and in addition
long period SE swells will be affecting the waters.
&&
.HYDROLOGY...
No hydrologic concerns through Thursday night.
The Weather Prediction Center has placed western sections of the
forecast area (the Lower Hudson Valley and northeastern New Jersey)
in a marginal risk of excessive rainfall for Friday and Saturday. As
a more humid air mass moves into the region precipitable waters
values will be increasing to around 1.75 to just over 2 inches.
There is a chance that areas in the marginal risk could see up to
2.00" of rainfall in a short period of time as warm cloud processes
dominate. However, there is a great deal of uncertainty with the
movement of the upper and surface lows that will affect rainfall
rates. Even if flash flooding does not occur, widespread nuisance
flooding remains possible with flooding of urban areas and low lying
and poor drainage areas.
&&
.TIDES/COASTAL FLOODING...
There is a high risk of rip current development for all ocean
beaches on today and Thursday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...High Rip Current Risk through this evening for NYZ075-080-081-
178-179.
NJ...None.
MARINE...Small Craft Advisory from 1 PM this afternoon to 8 PM EDT this
evening for ANZ338.
Small Craft Advisory until 8 PM EDT Thursday for ANZ350-353-
355.-- End Changed Discussion --
&&
$$
SYNOPSIS...DR/MET
NEAR TERM...DR
SHORT TERM...DR
LONG TERM...MET
AVIATION...MET
MARINE...DR/MET
HYDROLOGY...DR/MET
TIDES/COASTAL FLOODING...DR