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Area forecast discussion 
National Weather Service New York New York
413 am EDT Sat Oct 22 2016

deepening low pressure will track north across coastal New
England today and then into eastern Canada tonight into Sunday.
Another cold front will move southeast across the area early
Monday followed by Canadian high pressure through Wednesday. Low
pressure will move slowly east toward the area Thursday through


Near term /until 6 PM this evening/...
cold front has worked as far east as New Haven in Connecticut and
Islip on Li. The front is forecast to pass east of Li and
southeast CT around daybreak. Occasional gust up to 25 mph will
occur behind the front early this morning, mainly from NYC and
points north and west.

Latest radar imagery depicts a south to north oriented band of
moderate to occasionally heavy showers expanding northward across
New Jersey. Observations and radar indicate as much as half an inch an
hour in spots. This area will continue to work north this morning
and then gradually pivots NE as a negatively tilted upper trough
approaches from the west. This combined with a steeply sloped
frontal surface will produce deep-layered Post-frontal lift that
translates slowly east with time. Therefore, expecting showers to
become more widespread from west to east as the morning

Conditions will begin to gradually dry out this afternoon as the
upper low passes to the north.

More importantly though, will be strong west winds on the
backside of deepening low pressure across coastal New England
today. Pressure rises this afternoon and tightening of the
pressure gradient will result in the potential for gusts around 45
mph across Li/NYC Metro, and 35 to 40 mph elsewhere. The top of
the mixed layer approaches 50 kt near the coast late this
afternoon. Some of the higher elevations across the lower Hudson
Valley and NE New Jersey may even occasional gusts up to 50 mph as well. A
Wind Advisory will be issued for NYC/coastal Li/southeast CT, where the
highest pressure rises occur this afternoon into early this

High temperatures will occur around daybreak and then gradually
fall today into the upper 40s and lower 50s. Most locations by
afternoon will be 10 degrees below normal.


Short term /6 PM this evening through Sunday night/...
any left over showers tapper off from south to north tonight as
moisture and forcing lift northward with the low. Gusty west winds
up to 45 mph will continue as the low slowly lifts to the north.
Wind Advisory remains up overnight for Li/NYC Metro and portions
of southeast CT. Winds during the day on Sunday will gusts up to 40 mph
for most locations.

Upper trough lifts across eastern Canada on Sunday with gradually
weakening surface low. High pressure builds east across the

Lows tonight will be near seasonable levels as gusty winds
inhibit strong radiational cooling.

Highs on Sunday rebound to near normal with highs in the mid 50s
to lower 60s.

Clipper low approaches Sunday night and sends a cold front
through the area by daybreak Monday. There is decent lift in the
85h-500h layer with a good chance of showers.


Long term /Monday through Friday/...
Monday through Wed will be quite cool as a building Canadian high
pressure system moves east across New England, bringing overnight
low temps into the 30s across most of the local area, even across
parts of NYC on Tuesday night. Grab those jackets.

Thu-Fri will bring our next chance of rain as low lvl warm air
advection increases between the departing Canadian high and a low
approaching across the Great Lakes.


Aviation /07z Saturday through Wednesday/...
a cold front has already moved across most terminals and will
move east of Long Island before dawn Saturday. The winds will
switch from a light SW-west flow to a gusty northwest flow which will peak
on Saturday generally in the 20-25 kt sustained range with gusts
near 35kt at times, mainly in the afternoon to early evening. The
northwest flow will lead to an improvement of category, eventually to VFR
Saturday mid to late afternoon.

Currently, conditions range from MVFR to LIFR. With exception of
kgon, expecting other sites that are IFR to improve to MVFR by
07-08z. This could last an extra hour beyond forecast. For
Saturday, the MVFR end time could be off by 1-4 hours.

In terms of winds, they could occasionally be off by a few kts.

Outlook for 06z Sunday through Wednesday...
Saturday night-Sunday...VFR. West-northwest-northwest winds g25-35kt likely.
Sunday night-Tuesday night...VFR, northwest winds g20-25kt possible.
An isolated shower possible Sunday night into Mon morning.


westerly gales develop across all waters today as deepening low
pressure lifts north along the New England coast.

Gales are forecast to continue through the day Sunday. Wind gusts
may briefly drop below 25 kt Sunday night before a cold front passes
early Monday morning. Wind gusts of 25-30kt are likely Monday
through Tuesday. Winds and seas are forecast to decrease on
Wednesday as high pressure moves across the area.


additional rainfall today is expected to be in the range of a
quarter to half an inch with isolated higher amounts. The highest
amounts will be generally over the husdon valley.

Sunday night...scattered showers with rainfall of less than one
tenth of an inch is forecast with the passage of a cold front.

Thursday through Friday...a widespread rainfall of 1/2 to 1 inch
is possible with the approach of low pressure from the Great


Okx watches/warnings/advisories...
New York...none.
New Jersey...none.
Marine...Gale Warning until 6 PM EDT Sunday for anz330-335-338-340-345-
Small Craft Advisory for hazardous seas until 6 am EDT early
this morning for anz350-353-355.



near term...dw
short term...dw
long term...gc

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