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fxus61 kokx 261422 
afdokx

Area forecast discussion
National Weather Service New York New York
1022 am EDT sun Mar 26 2017

Synopsis...
high pressure centered over eastern Canada and extending into
New England and the northeast will gradually slide east today. A
stationary front well to the southwest will approach as a warm
front tonight and move north Monday. Another frontal system
affects the region Tuesday and Tuesday night. High pressure
builds to the west Wednesday and Thursday. Another low pressure
system approaches Friday.

&&

Near term /until 6 PM this evening/...

Center of Canadian high pressure gradually slides to the coast
by late in the day. Temps will run a good 5 to 10 degrees below
seasonable today with cold air damming and cloud cover. Max and
hourly temp trends have been adjusted down slightly.

A swath of light rain will continue to drifting northeast
through eastern Li and se CT through early this afternoon,
coincident with an elevated warm front and corresponding zone of
Theta E advection. Spotty freezing rain and sleet and icy spots
expected across interior portions of central and eastern CT
this morning...before temps rise above freezing by midday.

Additional spotty light rain activity could works from SW to NE
across the region this afternoon associated with some weak vort
energy...but overall coverage and probabilities look low under
shortwave ridge axis.

&&

Short term /6 PM this evening through 6 PM Monday/...
the closed and nearly cut off low that was over Missouri will
continue to open and weaken as the shortwave gets picked up by a
weak southern stream flow, and the wave moves into the eastern
ridge. There remains some timing difference with the movement of
the warm front and low tonight into Monday. Also, with weak
forcing unsure how much precipitation will occur. So have
lowered probabilities into the likely category, with the higher
chance west and north late tonight into Monday.

&&

Long term /Monday night through Saturday/...
with the wave continuing to dampen late Monday into Monday night
with weak ridging ahead of the next shortwave, there may be a
break in the precipitation. However, with the uncertainty, and
to keep continuity have continued with slight chance
probabilities Monday night.

Yet another shortwave approaches in the weak southern stream as
this wave also dampens as wave approaches the mid Atlantic.
There are timing differences and whether or not the shortwave
will phase with a digging northern stream shortwave Tuesday.
With uncertainties will keep probabilities at low chance Tuesday
into Tuesday night.

Wednesday and Thursday look to be dry with high pressure building
in. Cold air advection appears to be delayed enough to the point
where highs on Wednesday end up above normal, then near-normal for
Thursday. Friday could be completely dry as well, but perhaps some
rainfall sneaks into the western zones by the end of the day. High
temps again near normal. Global models then disagree with the track
of an area of low pressure that could bring rainfall on Saturday.
Have capped pops at 40% for now.

&&

Aviation /14z Sunday through Thursday/...
high pressure will build southward across the area today with a
brief push of drier air this morning. However, daytime heating
will likely lead to the redevelopment of MVFR conditions across
the area, lowering to IFR tonight. There is potential for brief
improvement this evening for a few hours before dark, so
subsequent taf amendments may be needed. Conditions overnight
may fall below minimums ahead of an approaching warm front and
will need to be monitored.

North-NE winds around 10 kt will become more easterly, with a few
gusts g15-20kt possible in the afternoon at the coastal/NYC
Metro terminals.

Outlook for 12z Monday through Thursday...
Monday...IFR/LIFR to start. Conds could improve to MVFR or VFR
by late morning or afternoon if the warm front moves through.
Monday night-Tue night...IFR likely, LIFR possible with low
clouds/fog.
Wednesday...VFR. Northwest winds g20-25kt, possibly stronger.
Thursday...VFR.

&&

Marine...
northeast flow strengthens today between high pressure to the
north and the cold front to the south/low pressure to the west.
Marginal Small Craft Advisory gusts are expected on the ocean waters through
tonight. The resultant easterly fetch should allow for ocean
seas to build to 4 to 7 ft. Winds are expected to weaken and
veer se on Monday as a warm front works into the waters...but
E/se swells will likely keep seas at Small Craft Advisory levels through the
evening.

Otherwise, sub-sca conditions are expected across all waters briefly
on Tuesday before gradually building through the evening in
strengthening southerly flow ahead of a low pressure approaching
from the west. Strong west-northwesterly flow with gusts to 25 kt
will develop on Wednesday as a cold front passes which will
initially allow seas to stay elevated at Small Craft Advisory levels before gradually
shifting east of the ocean waters. Stronger winds may persist into
Thursday before weakening by late week as high pressure briefly
builds over the area.

&&

Hydrology...
one quarter of an inch to one half an inch of rainfall is
possible today through Tuesday night.

No hydrologic issues are anticipated through Tuesday.

&&

Tides/coastal flooding...
latest surge guidance indicating that water levels should stay
safely below minor flood thresholds for tonight and Monday
morning high tide.

As astronomical tides rise through the week...water levels may
come close to minor levels during high tides in the most
vulnerable spots on Tue/Tue night ahead of approaching low
pressure.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 7 PM EDT Monday for anz350-353-355.

&&

$$
Synopsis...met
near term...met/NV
short term...met
long term...jc/met

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