Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
719 am EDT sun Mar 29 2015
high pressure west of the region builds south through today and
moves off the southeast coast this evening. A low pressure system
approaches from the northwest tonight with a cold front crossing
the region Monday. A series of low pressure systems will impact
the area through the upcoming week.
Near term /until 6 PM this evening/...
snow has ended across eastern Suffolk County and the Winter
Weather Advisory was allowed to expire.
The upper trough axis was now off the northeast coast as seen on
the water vapor...and height were rising as the upper ridge
builds east. The ridge builds in through the day with the axis
moving over the area early this evening. At the surface...high
pressure will remain west of the area....centered over the Ohio
Valley...and build south.
A northwest flow persists today...however weak low level warm
advection sets up this afternoon. With clearing conditions and
weak subsidence have leaned toward the higher mav guidance for
highs this afternoon...in the lower to middle 40s...well below
Short term /6 PM this evening through 6 PM Monday/...
weak warm advection strengthens tonight as the surface high
remains off the southeast coast. Northern stream upper flow is
active and the upper ridge quickly breaks down as the next
shortwave approaches. A warm front develops late tonight west of
the area and light precipitation may break out before sunrise.
Colder air will be in place and a wintry mix will be likely at the
start. Some freezing rain is possible in the valleys of
northeastern New Jersey with the colder air trapped at the surface
as warmer air moves in aloft. As warmer air moves in the
precipitation transitions to all liquid.
The upper trough moves through quickly Monday with a surface cold
front passing through by Monday evening. With limited moisture and
most of the lift north of the area will keep chance probability of precipitation early
morning into the afternoon.
Long term /Monday night through Saturday/...
by Monday evening a cold front will be east of the area with
precipitation having ended as an upper trough moves into New
Another shortwave and vorticity maximum will pass through the region
Tuesday night. Rain is expected to spread across the area Tuesday
night into early Wednesday morning...across inland locations there
could be a brief wintry mix overnight on Tuesday. Highs and lows
will be near seasonable levels Monday through Wednesday.
High pressure builds across the area on Wednesday then moves
offshore Thursday...with return flow and warm moist air quickly
spreading north across the area. Next low pressure is expected to
impact the local area either Thursday or Friday...with rain chances
Thursday night into Saturday.
Highs on Thursday and Friday will be in the upper 50s to low
60s...with lows in the low to middle 40s.
Aviation /11z Sunday through Thursday/...
low pressure slowly moves east as high pressure builds towards the
VFR. Skies gradually clear this morning...with few clouds
Northwest winds this morning...with some occasional gusts. The
winds eventually shift briefly to the west during the
afternoon...then shift to the SW late in the taf period.
Clouds move back into the region late tonight...but ceilings remain
Outlook for 12z Monday through Thursday...
Monday...VFR. West winds 10-15 knots with gusts up to 20 knots.
Tuesday night...MVFR or lower conds in -ra.
Thursday...MVFR or lower conds in -ra.
forecast on track. Wind and gusts continue to slowly diminish.
High pressure was building into the waters from the west early
this morning as low pressure near the Canadian maritime moves well
to the north. Gusts remain east of Fire Island Inlet with
marginal small craft seas 5 to 6 feet. Wind gusts diminish this
morning with seas slowly subsiding through this afternoon. The
Small Craft Advisory remain for the waters east of Fire Island
Inlet through this afternoon.
As a low approaches from the west tonight a southerly flow will
develop. This flow increases early Monday morning and small craft
conditions will be likely on the ocean waters by early Monday
morning. Gusts across the remainder of the forecast waters may
approach small craft levels Monday. Lingering small craft seas
are possible on the ocean waters into early Tuesday.
Otherwise below small craft level conditions expected Tuesday
through Thursday...as winds and waves diminish and weak high
pressure builds across the area waters.
no significant widespread precipitation is forecast through the
Rivers and streams are expected to remain below bank full...but
increased river/stream flow across the lower Hudson Valley and
southern Connecticut will continue ice breakup and movement into
this weekend. Isolated ice jams are possible...which if they
occur...could result in localized flooding. Since ice jam flooding
is unpredictable and sudden...interests along ice covered rivers
should monitor National Weather Service forecasts for the latest information.
For details on specific area rivers and lakes...including
observed and forecast river stages and lake elevations...please
visit the advanced hydrologic prediction service /ahps/ graphs on
our web site.
Marine...Small Craft Advisory until 6 PM EDT this evening for anz350-