000
FXUS61 KOKX 061734
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
134 PM EDT Tue Jun 6 2023
.SYNOPSIS...
Low pressure over the Canadian Maritimes remains nearly
stationary through midweek, sending a cold front through the
area this afternoon. The low will then weaken the second half of
the week drifting south into the Gulf of Maine. Weak high
pressure builds in Saturday and moves offshore Sunday as a cold
front approaches. The front moves through the region late Sunday
into Monday.
&&
.NEAR TERM /THROUGH TONIGHT/...
Main concerns into this evening are with scattered convection
and smoke/haze.
Steep lapse rates (7C) from the surface into the mid
levels will combine with marginal to moderate instability to
produce scattered showers and isolated thunderstorms.
Instability has been slowly increasing per SPC mesoanalysis.
Looks like about 500-750 J/KG of CAPE will occur this afternoon.
The CAMs continue to indicate a bit greater coverage across CT
and Long Island this afternoon/early evening. However, still
cannot rule out some convection elsewhere with the upper trough
and surface front moving through the area.
Storms should remain sub-severe, but CSU machine learning
severe probabilities still show a marginal risk for hail and
wind. An isolated severe thunderstorm cannot be ruled out with
the main concern from a damaging wind gusts due to dry subcloud
layer. Large hail threat looks limited since CAPE may be
limited. Rainfall amounts will should be under a quarter inch.
Smoke from wildfires across eastern Canada working across across
the area with some visibility restrictions down to 4-6sm. Some
locations across NE NJ and Lower Hudson Valley may briefly
improve with just haze/smoke aloft. Some of this improvement may
reach eastern portions of the area briefly early this afternoon.
The latest HRRR near surface smoke fields indicate higher
concentrations occurring later this afternoon and evening. This
area of smoke can be seen on visible satellite imagery and
surface obs across upstate NY and southeast Canada. Have
maintained smoke and haze in the forecast into tonight. Areas of
smoke likely continue into the evening.
NW winds at times today may gusts as high as 20 to 25 mph. This
combined with the low RH values (30 to 35 percent) across NE NJ
will enhance the spread of any brush fires that do develop.
Highs today will be near seasonable levels in the 70s, perhaps
around 80 across metro NE NJ. Lows behind the cold front tonight
will be a few degrees below, ranging from the upper 40s inland,
to the upper 50s across NYC.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
Deep-layered cyclonic flow and disturbances rotating about the
upper low will bring clouds each afternoon with a chance of
showers. There will be a bit more instability Thursday afternoon
and perhaps an isolated thunderstorm north and west of the NYC
metro. Temperatures will gradually cool down through Thursday.
For Thursday, leaned toward the cooler MOS versus the NBM due to
more cloud cover as the upper low retrogrades west across
northern New England.
Smoke and haze issues may linger into Wednesday, especially for
the western half of the forecast area.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Omega blocking will persist into Saturday as a large closed
upper low remains over the northeast and into eastern Canada.
The low weakens Saturday and drifts northeast as additional
energy rotates into the upper trough. That low deepens and
becomes closed off Sunday and remains into Monday. Overall, the
extended period will be unsettled except for a brief dry period
late Saturday into Sunday as weak ridging builds into the
northeast. Temperatures will be generally just below seasonal
normal levels, except for Sunday with the ridge and dry weather.
There is a chance of showers into Saturday with a slight chance
of thunderstorms inland late Friday where there will be better
instability and forcing. Additional showers and thunderstorms will
be possible with a cold front Sunday and Monday. Generally
followed the NBM guidance except with a few adjustments to the
probabilities.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
A cold front will approach this afternoon and move through
during through the late afternoon.
SHRA and TSRAs have developed across the LoHud Valley and are
moving SE into SW CT. Best chance of thunder should be at the
CT and Long Island terminals, especially KGON where brief IFR
cond may be possible.
Light WNW should increase by early afternoon, with gusts near
or just over 20 kt through 00Z. Winds shift NW after fropa,
them diminish later this evening.
Smoke from Quebec wildfires will limit slant range visibility at
times today, especially for NYC terminals and KISP/KGON/KBDR.
Less confidence in reduction in vsby for KEWR/KTEB/KSWF based on
latest satellite trends for the smoke.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
AMD may be needed this afternoon for tstm timing/coverage.
OUTLOOK FOR 06Z TUESDAY THROUGH SATURDAY...
Late tonight: VFR.
Wednesday: VFR. W-NW winds G20kt. MVFR vsby again possible in
smoke/haze at the NYC metros from 20Z-24Z.
Thursday through Friday: Mainly VFR. Chance of afternoon and early
evening showers both days.
Saturday: VFR.
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 likely remain below SCA levels through Saturday
night as low pressure over the Canadian Maritimes weakens. Weak
low pressure will then remain in the vicinity of the forecast
waters through Saturday.
&&
.FIRE WEATHER...
NW winds at times today may gust as high as 20 to 25 mph. This
combined with the low RH values (30 to 35 percent) across NE NJ
will enhance the spread of any brush fires that do develop.
&&
.HYDROLOGY...
No hydrologic impacts expected through the beginning of next week.
&&
.TIDES/COASTAL FLOODING...
Low pressure over the Canadian Maritimes continues to produce E
swell that in tandem with high astronomical tides is keeping water
levels higher than usual, especially in the back bays of Nassau.
Followed the Stevens NYHOPS bias-corrected central forecast and
issued a coastal flood advisory is in effect for the high tide cycle
late this evening. Water levels there may barely touch minor
thresholds with the high tide cycles both Wed/Thu nights as well.
There is a low risk for the development of rip currents at the
ocean beaches today and Wednesday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Coastal Flood Advisory from 9 PM this evening to midnight EDT
tonight for NYZ179.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...MET/DW
NEAR TERM...DS/DW
SHORT TERM...DW
LONG TERM...MET
AVIATION...DBR/EA
MARINE...MET/DW
FIRE WEATHER...
HYDROLOGY...MET/DW
TIDES/COASTAL FLOODING...