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fxus61 kokx 231119 
afdokx

Area forecast discussion
National Weather Service New York New York
719 am EDT Sat Jun 23 2018

Synopsis...
a warm front approaches today, and lifts to the north tonight into
Sunday. A cold front passes Sunday afternoon and evening. High
pressure then builds through mid week, giving way to a warm front
Wednesday night into Thursday. A weak cold front passes Friday.

&&

Near term /until 6 PM this evening/...
increasing coverage for showers, with isolated thunderstorms,
is expected this morning ahead of an approaching warm front,
and passing upper shortwave moving into the eastern Great Lakes.
Already observing heavier showers/isolated thunderstorms,
tracking northward toward the region. The warm front continues
to approach, with an easterly flow through the day across the
region, veering around to the southeast late. The
shower/thunderstorm activity will likely dissipate in coverage
by late morning and into the afternoon. However, coverage may
increase late in the day as next shortwave passes along with the
warm frontal approach.

Highs today will only be in the upper 60s to the lower 70s due to
cloud cover, on and off rain, and easterly flow.

There is a moderate risk of rip currents at Atlantic Ocean beaches
today.

&&

Short term /6 PM this evening through Sunday night/...
passing upper shortwave along with warm front approaching the
coastal locations will result in higher coverage of showers and
thunderstorms in the evening. Locally heavy downpours will be
possible with precipitable water values approaching 2 inches.
The warm front should lift toward Long Island tonight with the
showers departing late, with isolated showers at best the remainder
of the night.

On Sunday, the warm front is expected to lift to the north.
Persistent west/SW flow aloft expected, and will slowly steer a
cold front through late in the day and at night.

Moderate instability builds northwest of NYC, and showers and thunderstorms
redevelop during the afternoon, before dissipating at night.

Lows tonight will remain in the 60s, and warmer temps are
anticipated Sunday with west/SW flow as area sits temporarily in the
warm sector. Lower to middle 80s are expected. Lows fall into the
60s Sunday night.

&&

Long term /Monday through Friday/...
high pressure builds in during Monday, but with a cyclonic flow
aloft there could be a shower or two across southeast CT. Partly cloudy
with near normal temperatures. The high pressure center moves
through on Tuesday with sunny conditions and highs close to normal.

The high will be to our east on Wednesday, and a return SW flow
will bring warmer and more humid conditions. It appears the
daytime hours for most areas will be dry as showers ahead of an
approaching warm front remain to the west. The warm front moves
through, then a cold front slowly approaches Thursday into
Friday. Timing of the cold front is not certain, so will go with
slight chance to chance pops Wednesday night through Friday.
Rising temperatures aloft will allow for highs in the 90s for
the city and some inland areas Thursday and Friday. If the cloud
cover is lower then currently anticipated, then highs could be
a even a few degrees higher than what's in the forecast.

&&

Aviation /12z Saturday through Wednesday/... high pressure
centered near Nova Scotia and extending into New England will
drift east through today as a warm front and low pressure
approach. The warm front will likely remain to the south of the
terminals through 00z Sunday. There is a low chance the front
moves through late in the forecast period.

MVFR ceilings will gradually lower to IFR through the morning as
stratus moves through the terminals. A brief period of MVFR will be
possible during the afternoon, before conditions fall to IFR or
lower tonight as the warm front moves over the area, decreasing
winds.

Showers will likely be more occasional than steady, but could
produce heavy downpours with reductions in visibilities at
times. A rumble of thunder will be possible with the showers, with
the best chance of thunder late in the afternoon into the
evening.

Winds generally remain NE to east through today until the warm front
approaches late in the day. Winds will be 10 to 15 knots along the
coast and 5 to 10 knots inland, becoming light and variable tonight as
the warm front begins to move through.

Outlook for 12z Sunday through Wednesday...
Sunday...chance of MVFR or lower conds in mainly late
day/evening showers/tstms.
Monday-Tuesday...VFR.
Wednesday...mostly VFR. Chance of showers/tstms with MVFR or
lower conds mainly at kswf.

&&

Marine...
brief Small Craft Advisory level seas and occasional gusts to near 25 kt will develop
today in strengthening easterly flow. By late afternoon/evening, the
approaching warm front will allow flow to weaken, with a subsequent
decrease in seas. Seas may briefly return to around 5 ft tonight
with a building southerly swell.

Conditions will remain tranquil Sunday through Tuesday as the warm
front moves to the north, followed by a cold frontal passage and
building high pressure. Thereafter, the high shifts offshore, with
south-southwest flow strengthening, and Small Craft Advisory-level gusts possible on
all waters Wednesday and Thursday afternoon. Ocean seas will
increase to Small Craft Advisory-levels in response to the strengthening and
prolonged south-southwest flow.

&&

Hydrology...
there could be a few locally heavy downpours today, tonight and
again Sunday. However, no hydrologic impacts are anticipated.
Rainfall totals through tonight will average around half an inch to
locally one inch, but breaks in the showers are expected.

&&

Equipment...
NYC National oceanic and atmospheric administration weather radio station kwo-35 (162.55 mhz) remains off
the air for an extended period of time.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 2 PM EDT this afternoon for anz350-
353-355.

&&

$$
Synopsis...precipitable water
near term...precipitable water
short term...precipitable water
long term...jc/pw

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