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fxus61 kokx 251433 
afdokx

Area forecast discussion
National Weather Service New York New York
1033 am EDT Tue Jul 25 2017

Synopsis...
high pressure will build over the area through Wednesday before
moving offshore Wednesday night. A warm front will lift toward
the area late Thursday, followed by low pressure and a cold
front on Friday. High pressure will build across this weekend
before another low passes to the south early next week.

&&

Near term /until 6 PM this evening/...
minor adjustments with this update.

Clouds will linger today as a weak low passes to the south and
east. Upper trough could kick off a light shower or two, per
high res models, along with nwp runs.

Otherwise, expect cool conditions with high temperatures in the
upper 60s/lower 70s as high pressure builds to the north and east-northeast
flow persists.

There remains a high risk of rip currents at ocean beaches
through today.

&&

Short term /6 PM this evening through 6 PM Wednesday/...
high pressure will provide another unseasonably cool night with
clearing skies. Low temperatures overnight will be in the
mid/upper 50s inland and lower 60s along the coast. The high
will remain in control on Wednesday before pushing offshore
Wednesday night. High temperatures on Wednesday will be in the
mid/upper 70s.

&&

Long term /Wednesday night through Monday/...
upper level shortwave that is expected to dive out of central
Canada, the Great Lakes region, then across the area Friday into
Saturday, will need to be watched as global models differ on
strength of this feature. Across eastern Canada, cutoff low develops
this weekend, with lingering trough extending across the northeast
states. As the weekend progresses, this low moves northeast.

At the surface, high pressure to the east gives way to a weak warm
front late Thursday. Sfc low pressure tracks across the Ohio Valley
Thursday, then toward the mid Atlantic coast early Friday. Due to
differences aloft in the models, placement of sfc low, and strength
of the low differs somewhat. At this time, it appears that consensus
would place the low just to our south, along a cold frontal boundary
Friday. This low moves east by Saturday, as high pressure builds
from the west/northwest. This high should remain in control Saturday
through Monday.

As for sensible weather, shower chances increase late Thursday, with
the best chance for showers, possible thunderstorms Thursday night
into Friday. Still uncertainty with this system, but there is the
potential for significant rainfall. Thereafter, dry conditions
prevail.

Do not foresee large temperatures differences/swings, with near
normal readings anticipated.

&&

Aviation /14z Tuesday through Saturday/...
high pressure builds over the terminals through much of the taf
period, shifting offshore Wednesday afternoon into Wednesday
night.

MVFR cigs should last much of the day with some improvements to
VFR late this afternoon and more widespread improvement to VFR
tonight. Mainly VFR conditions then prevail through Wednesday.

Winds east-northeast to NE 10 kt or less for most terminals. There is a
chance winds could go east-east-southeast at kbdr and southeast at kgon this
afternoon.

New York Metro enhanced aviation weather support...

Detailed information, including hourly taf wind component fcsts,
can be found at http:/www.Weather.Gov/zny/n90

Kjfk taf comments: amend likely to fine tune changes in flight
category. The haze potential forecast is green, which implies
slant range visibility more than 6sm outside of cloud.

Klga taf comments: amend likely to fine tune changes in flight
category. The haze potential forecast is green, which
implies slant range visibility more than 6sm outside of cloud.

Kewr taf comments: amend likely to fine tune changes in flight
category. The haze potential forecast is green, which
implies slant range visibility more than 6sm outside of cloud.

Kteb taf comments: amend likely to fine tune changes in flight
category.

Khpn taf comments: amend likely to fine tune changes in flight
category.

Kisp taf comments: amend likely to fine tune changes in flight
category.

Outlook for 12z Wednesday through Saturday...
Wednesday...VFR. Winds becoming more southeast-S near 10 kt or less in
the afternoon.
Thursday...MVFR conds possible, with chance of showers and
possibly a tstm.
Thursday night and Friday...MVFR or lower conds possible, with
a chance of showers and tstms, as low pressure passes by.
Confidence is low on exact timing and placement of any heavier
rain and tstms. Heavier rain appears more likely to pass just to
the south Fri morning, but it is too early to be certain. Worst
case would be a high impact event for the am push.
Friday night...mainly VFR.
Saturday...VFR.

&&

Marine...
small craft conditions expected across ocean waters through
this evening, primarily for seas. High pressure builds across
the area waters on Wednesday.

High pressure departs Wednesday night, giving way to a warm
front Thursday, then low pressure and associated cold front
Thursday night through Friday.

The low and cold front pass east Friday night as high pressure
builds.

Through the late week period, sub Small Craft Advisory conditions are generally
expected. The only exception could be late Thursday night into
Friday. Much depends on eventual strength of the low as it moves
across the waters.

Seas should remain 5 ft or less Wednesday night through Saturday,
but the late Thursday night through Friday time frame needs to be
monitored as the storm impacts the local waters.

&&

Hydrology...
no hydrologic impacts expected through Wednesday. Additional
rainfall is possible Thursday night through Friday, with a
corresponding low chance for urban and poor drainage flooding.

&&

Tides/coastal flooding...
astronomical high tides continue to run high, especially during
the high tide cycle at night. Along the South Shore bays of
Nassau and Queens, less than a foot departure is needed to reach
minor flooding thresholds. Departures there should run around 1
foot above. As such, a coastal flood advisory has been issued
for these areas for tonight's high tide cycle.

&&

Okx watches/warnings/advisories...
CT...none.
New York...high rip current risk until 9 PM EDT this evening for nyz075-
080-081-178-179.
Coastal flood advisory from 9 PM this evening to midnight EDT
tonight for nyz178-179.
New Jersey...none.
Marine...Small Craft Advisory until 6 PM EDT this evening for anz350-
353-355.

&&

$$

Synopsis...fig/pw
near term...fig/dw/pw
short term...fig
long term...precipitable water

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