000
FXUS61 KOKX 301453
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1053 AM EDT Fri Jun 30 2023
.SYNOPSIS...
High pressure will build offshore today, allowing for
increasingly humid flow off of the ocean thru the weekend. A
frontal boundary approaches Monday and stalls over or near the
area through the middle of next week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
The fog is breaking up with decreasing areal coverage late this
morning in response to diurnal heating and more vertical mixing.
The haze is resulting in lowered visibilities to around 3 to 5
miles and is expected to linger through the afternoon.
Minor adjustments were made to temperatures, dewpoints, and
cloud coverage to better match with observed trends. Forecast
mainly on track. Dry conditions are in place today with
subsidence with the influence of high pressure.
As high pres drifts offshore, sly return flow, albeit light,
will attempt to displace the llvl smoke and haze. Still, the
HRRR indicates the smoke should be around for most if not all of
the day.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
Dry wx continues tngt, but the onshore flow should allow for at
least some fog. The NAM seems a bit more realistic under this
regime, with the GFS keeping the moisture in the 4-7k ft range.
Prefer the NAM soln with a shallow moist layer near the sfc,
although the model is likely overdone per the usual bias. For
these reasons, kept the fog coverage at patchy for now.
Perhaps a renegade shwr overnight with some weak frogen, but
left out of the fcst for now with low confidence in occurrence,
timing, and coverage.
Still some lingering haze per the smoke model.
WSW flow aloft develops on Sat. It looks attm like the best
forcing will remain north of the cwa, and the flow off of the
water will keep the area generally stable. As a result, the
fcst has been kept dry.
Gradually increasing pops Sat ngt thru Sun as the upr trof gets
closer and any embedded energy encroaches on the cwa. Lots of
convection to feed into the flow from the plains to the midwest,
but the exact timing and magnitude of any significant waves
difficult to predict this far out. Followed the NBM for pops as
a result, but limited them to the lowest end of likely at 56
percent. Right now, the best window is Sunday aftn and eve, but
any time on Sun remains possible due to any introduction of upr
lvl support.
Temps tngt thru Sun ngt the NBM with some minor local
adjustments.
Increasing humidity thru the weekend, so Sun could end up a bit
swampy, especially LI to the CT coast.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
An unsettled period is expected in the long term. A frontal boundary
will linger over or near the area from Monday through the middle of
next week. However, latest guidance seems to be more progressive
with the system and trending drier for Wednesday and Thursday. The
center of the low passes to our north and west as an upper level
trough swings through.
A very warm, moist southerly flow will be ongoing Monday morning
with a warm front to our north. Guidance continues to show an
airmass with pwats 2-2.25 inches. Per SPC`s Sounding Climatology
Page, this is above the max moving average for this time of year.
Showers and thunderstorms are possible each day, but the time period
where they are most likely is Monday afternoon. Widespread
hydrologic impacts continue to not be expected. The newest guidance
from the WPC now has portions of northeast NJ and the Lower Hudson
Valley in a marginal risk of excessive rainfall only on Day 4
(Monday).
Temperatures have trended up slightly from the last forecast. Above
average temperatures are expected. Highs in the mid 80s to low 90s
and lows in the upper 60s to lower 70s.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
Weak high pressure passes offshore today.
Fog is eroding at 1430z, though smoke haze will continue to
reduce visibilities. MVFR vsbys, 3-5sm, likely linger into early
afternoon, gradually improving to VFR this afternoon or evening
with southerly flow.
Synoptic flow becomes S 5-10 kt by late morning/early afternoon.
Light and variable winds return for most tonight.
THE AFTERNOON KJFK, KLGA, KEWR HAZE POTENTIAL FORECAST IS
RED...WHICH IMPLIES SLANT RANGE VISIBILITY LESS THAN 4SM OUTSIDE OF
CLOUD.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Low confidence overall in vsby forecast in smoke haze. MVFR vsby
expected through at least early afternoon. Could improve from
there with southerly flow helping to reduce smoke concentrations.
OUTLOOK FOR 12Z SATURDAY THROUGH MONDAY...
Saturday: Chance of showers and slight chance of thunder for NYC
terminals north and west.
Saturday Night and Sunday: Showers likely and chance of tstms. MVFR
expected, IFR possible with this activity.
Monday and Tuesday: MVFR possible. Chance of mainly
afternoon/evening showers/tstms.
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 will stay blw sca lvls thru Sat. Seas may
approach 5 ft on the ocean Sun, but right now are modeled to
only get to 4 ft.
Sub-SCA conditions are expected to prevail Monday through Thursday
with a weak pressure gradient in place and a lack of significant
swell. However, there will be a slight chance to chance of
thunderstorms each day, which could result in locally hazardous
conditions.
&&
.HYDROLOGY...
No hydrologic impacts are expected thru Sat. There is a low
chance of some locally hvy shwrs and tstms Sun.
At this time, no hydrologic impacts are expected Monday through
Thursday. With a frontal boundary lingering over or near the area,
localized impacts may become possible toward Monday. It is still too
early to pinpoint exact details.
&&
.TIDES/COASTAL FLOODING...
A moderate risk of rip current development expected today
Saturday on the ocean waters.
With astronomical tides increasing this weekend as we head
toward a full moon on Monday, minor coastal flooding may be
possible with the evening high tide cycles from Saturday
through at least Monday. Areas most likely to be affected are
the south shore bays of Nassau, Queens and Brooklyn, Staten
Island, and Southern Fairfield/Westchester Counties.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JMC/JT
NEAR TERM...JMC/JM
SHORT TERM...JMC
LONG TERM...JT
AVIATION...DR/JT
MARINE...JMC/JT
HYDROLOGY...JMC/JT
TIDES/COASTAL FLOODING...