258
FXUS61 KOKX 071747
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
147 PM EDT Sat Sep 7 2024
.SYNOPSIS...
A cold front moves through the area this afternoon through this
evening. High pressure builds in thereafter. High pressure looks to
briefly weaken Monday night as a surface trough moves through. High
pressure then continues to build over the area Tuesday through
the end of the week.
&&
.NEAR TERM /THROUGH TONIGHT/...
Latest CAMs data is rather consistent with the timing and areal
coverage of precipitation moving through the region with a cold
front this afternoon into this evening. Updated based on this
data. The cold front was moving into central upstate New York
and into east central Pennsylvania at 15Z, with narrow line of
moderate precipitation. With little lift with the front have
removed the moderate rainfall. Although brief moderate rainfall
will be possible in any thunderstorms that remain possible,
mainly late this afternoon, 20Z to 23Z.
A deep upper level trough approaching from the west has now
closed off over the Great Lakes. The associated surface low was
moving into southwestern Quebec at 15Z. Meanwhile, offshore low
pressure well east of the area was south of Nova Scotia.
The cold front will likely reach western portions of the area
early this afternoon and pass east during the evening hours.
Pwats look to be a bit lower than guidance was showing 24 hours
ago. This is due to the plume of the deepest moisture likely
now not making it to the area before the cold frontal passage
and instead passing to the south and east. Pwats now look to be
closer to 1.25 to 1.5.
As for thunder, keeping at slight chance if there is any
thunder it will likely be along a thin convective line and brief
for any one location. While some gusty winds are possible,
severe thunderstorms are not expected due to weak instability
and only modest shear.
The whole area will likely be dry by midnight. A northwest flow
behind the front will bring in a cool and dry airmass. The
interior should be able to get down to the upper 40s tonight.
With the flow still around 10 kt, locations around NYC and Long
Island likely do not drop below the mid 50s.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
High pressure builds in at the surface, but an upper level
trough remains over the northeast. A dry and seasonably cool day
is expected on Sunday. Highs will only be in the upper 60s to
low 70s and dewpoints should drop into the low 40s in the
afternoon with deep mixing. Some 15-20 kt NW gusts are also
possible.
Radiational cooling conditions look ideal on Sunday night. Went
closer to the MOS guidance and have low to mid 40s at the usual cool
spots. Upper 40s to mid 50s elsewhere.
The flow becomes more W/SW on Monday. An embedded shortwave in the
larger upper level trough looks to rotate through late Monday into
Monday night. The surface high briefly weakens as an associated
surface trough passes through. The latest global guidance does
show some light QPF, but given the dry airmass left forecast dry
for now, which was in line with the NBM. However an increase in
clouds is expected.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
Key Points:
* A dry stretch Tuesday through Friday.
* A warming trend with high temperatures above normal by week`s end.
Models continue to be in decent agreement with upper ridging
building in to the northeast on Tuesday and amplifying by week`s
end. At the surface, high pressure will continue to shift north
Tuesday through Friday resulting in an extended dry stretch of
sensible weather. Highs each day will be near or just above
seasonable, in the low to mid 80s. The urban corridor may be a few
degrees warmer on Thursday and Friday, in the upper 80s, under weak
westerly flow. Dewpoints will also be on the increase Thursday into
Friday, as southerly flow ramps up as the surface high begins to
move offshore.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --
A cold front passes through the terminals late this aftn and
eve.
Generally sct-bkn around 1500ft until the fropa this aftn/eve.
Tstms possible mainly 19-23Z, with later timing for far ern
arpts. Becoming VFR after the fropa and continuing thru Sun.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Some adjustments to TSTM timing possible. Low chance of IFR thru
21-23Z with low cigs.
OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY...
Rest of Sun...VFR with NW winds gusting to around 20kt.
Mon...Mainly VFR. Chance of isold-sct aft/eve shwrs.
Tue-Thu...VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
No changes to winds and sea, however, updated the probabilities
of precipitation and removed mention of moderate rainfall. Brief
moderate rainfall does remain possible in a narrow line of and
thunderstorms that may move through the waters late this
afternoon and early this evening.
A Small Craft Advisory is in effect across the ocean waters due
to a 5 to 6 ft easterly swell around 10s. As offshore low
pressure pulls away, the swell will begin to decrease on Sunday.
However, lingering 5 ft waves are possible through about 18s
Sunday and have extended the SCA until then. Winds stay below
SCA criteria for the most part. Gusts may briefly reach 25 kt
with the passing of the cold front this afternoon into the
evening.
Winds and seas are then expected to remain below SCA criteria
through midweek, as the pressure gradient remains weak across the
region.
&&
.HYDROLOGY...
No significant hydrologic issues are expected through the end of
next week.
&&
.TIDES/COASTAL FLOODING...
There is a high risk of rip currents today as an easterly swell of 5
to 6 ft at 10s combines with an increasing southerly flow that peaks
out at 10 to 15 kt this afternoon. The risk drops to moderate on
Sunday. While the flow will be offshore, a short period wind wave
will combine with a decreasing easterly swell (2 ft at 10s) to allow
for at least a moderate risk of rip current development. This is
supported by the latest RCMOS guidance. RCMOS shows high for all
beaches today and then lowering through the day tomorrow, but
staying mostly in the moderate category.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents until 9 PM EDT this evening for NYZ075-
080-081-178-179.
NJ...None.
MARINE...Small Craft Advisory until 2 PM EDT Sunday for ANZ350-353-355.
&&
$$
SYNOPSIS...DBR/JT
NEAR TERM...MET/JT
SHORT TERM...JT
LONG TERM...DBR
AVIATION...JMC
MARINE...DBR/JT
HYDROLOGY...DBR/JT
TIDES/COASTAL FLOODING...