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Area forecast discussion 
National Weather Service New York New York
819 am EDT Tuesday Jun 2 2015

Synopsis...
a wave of low pressure will track just to the south of the region
along a frontal boundary today. High pressure builds in tonight.
Through Wednesday. High pressure will move off the New England
coast Wednesday night as an upper level low pressure system moves
slowly towards the southeast coast through Friday. A cold front
will move slowly across the area Friday night into Saturday
followed by high pressure for the weekend. A frontal system then
approaches for the beginning of next week.

&&

Near term /until 6 PM this evening/...
updated the forecast this morning to adjust probability of precipitation and cancel the
Flash Flood Watch. Looking upstream...activity is minimal with a
few areas of rain on the regional radar this morning. Even the
band that extends from the middle Hudson Valley of New York state
back through Pennsylvania has even been weakening this morning.
This is likely due to the Theta-E axis shifting southeast. Have lowered
probability of precipitation to chance across most of the region this morning and also added
drizzle. The afternoon remains uncertain as some of the models
break off a piece of energy from the cutoff low pressure system over
the southeast and track it up the coast. There is some hint of this on
water vapor and even some rain occurring as a result in the
Carolinas...but think the quantitative precipitation forecast fields are overdoing the amounts up
here as we will remain on the more stable side of the frontal
boundary with NE flow.

Even though precipitable waters remain high...and there could be some moderate
showers with any activity this afternoon...feel that the threat
for flash flooding has ended so have cancelled the watch. Have
also lowered quantitative precipitation forecast amounts significantly.

Showers...clouds...and a northeast flow will help to keep
temperatures will below normal for this time of year. Highs will
only be in the middle to upper 50s. 60 may be possible across
northeast New Jersey.

&&

Short term /6 PM this evening through 6 PM Wednesday/...
the chance for showers decreases as high pressure builds in from
southeastern Canada and the frontal boundary continues to push
away from the area. Dry conditions return late tonight and
continue through Wednesday. A northeast flow shifts to the east
Wednesday afternoon. This will allow the below normal temperatures
to continue with lows Tuesday night in the upper 40s to lower 50s.
Conditions will be warmer on Wednesday...middle 60s to near 70.

&&

Long term /Wednesday night through Monday/...
models are in good agreement with the 500 mb pattern across noam through
the end of the week. Slight differences in timing and amplitude
begin to become apparent in the northern stream on Sat and continue
into early next week leading to lower confidence in the forecast.

Wednesday night through Friday...high pressure will move off the New England
coast Wednesday night and slowly track eastward. Meanwhile...an upper level low
over the mid-Atlantic/southeast states will slowly track towards the coast.
The models are trying to bring precipitation from a weak surface low/inverted
trough off the middle Atlantic coast into the area Thursday/Thursday night...but
think this is too quick with ridging and subsidence still nosing in
from the E/NE. Have lowered probability of precipitation as a result. By Friday...the high
should be far enough away to allow some shower activity into the
area with a warm front extending up the coast from the low off the
middle Atlantic coast. Coverage not expected to be very widespread with
little upper level support.

Friday night through Saturday...an upper trough digging through southeastern
Canada will track through New England. A cold front extending from
the associated surface low in the Canadian Maritimes will approach Friday
night. Have the front slowly moving through the area into Sat...but
there is some indication that is washes out before making it
through.

High pressure with dry and seasonable weather then builds back in from
the north for the remainder of the weekend. A frontal system may impact
the area early next week.

Temperatures will start off below normal Wednesday night and Thursday with
onshore flow continuing. Near normal temperatures are then forecast for the
remainder of the period.

&&

Aviation /12z Tuesday through Saturday/...
a frontal boundary remains across the Delaware-Maryland-Virginia to south of Long
Island and Cape Cod with waves of low pressure moving along the
boundary into this afternoon. High pressure to the north builds
slowly south through the forecast period.

Highly variable conditions expected today...especially this
morning...with ceilings and visibilities varying from IFR to
marginal VFR with light rain and fog. By late morning ceilings are
expected to become marginal VFR with VFR visibilities. There will be
periods of light rain into middle afternoon.

Wind will be from the northeast through the forecast...030 to 060
true...10 to 15 knots.

Low confidence in the forecast with uncertainty in the timing of
changing conditions.



New York metropolitan enhanced aviation weather support...

Detailed information...including hourly taf wind component forecasts can
be found at: http://www.Erh.NOAA.Gov/zny/n90 (lower case)

Kjfk fcster comments: uncertainty with the timing of improvement to
marginal VFR ceilings this morning...could be slower than forecast.
Occasional gusts up to 20 knots possible this morning. High confidence
in the wind forecast.

Klga fcster comments: uncertainty with the timing of improvement to
marginal VFR ceilings this morning...could be slower than forecast.
Occasional gusts up to 20 knots possible this morning. High confidence
in the wind forecast.

Kewr fcster comments: uncertainty with the timing of improvement to
marginal VFR ceilings this morning...could be slower than forecast.
High confidence in the wind forecast.

The afternoon kewr haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.

Kteb fcster comments: marginal VFR ceilings could briefly become IFR
through 15z...otherwise ceilings remain marginal VFR. High
confidence in the wind forecast.

Khpn fcster comments: IFR conditions this morning. Expecting
conditions to improve to marginal VFR this morning...and could be
slower than forecast. However...visibilities should improve to at
least marginal VFR to VFR first...around 12z. Low confidence in
timing of improvements.

Kisp fcster comments: uncertainty with the timing of improvement
to marginal VFR ceilings this morning...could be slower than
forecast. High confidence in the wind forecast.

Outlook for 12z Wednesday through Saturday...
Wednesday-Thursday...VFR.
Friday...chance of showers with marginal VFR conditions.
Saturday...showers ending in the afternoon with conditions
improving to VFR.

&&

Marine...
Small Craft Advisory east/NE flow will continue through Wednesday with seas of 4 to 7
feet and wind gusts 25-30 knots on the ocean.

Showers will continue through the first half of tonight as a
stalled frontal boundary slowly pushes to the east.

Winds and seas may continue to reach Small Craft Advisory conds on the ocean waters
Wednesday night into Thursday with a tight pressure gradient over the area. The
gradient relaxes thereafter with sub-advsy conds on all waters
through the remainder of the period.

&&

Hydrology...
additional basin average quantitative precipitation forecast of up to 1/4 inch is expected today. The
Still River at Brookville in northern Fairfield County remains
above flood stage with minor flooding forecast. It is expected to
fall back within its banks this morning. No additional Hydro
related issues are expected today.

No significant rainfall (greater than 1/2 inch) is expected through
the weekend.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 6 PM EDT Wednesday for anz350-353-
355.

&&

$$

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