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fxus61 kokx 222008 
afdokx

Area forecast discussion
National Weather Service New York New York
408 PM EDT Wed Mar 22 2017

Synopsis...
gusty northwest winds will continue through this evening in the
wake of a cold front. High pressure builds in tonight from the
Great Lakes, moving more into the region on Thursday. The high
moves offshore Thursday night. A warm front passes Friday,
followed by a cold front Saturday. The front will wobble across
the area on Sunday before lifting back north on Monday as a warm
front. Additional areas of low pressure may impact the area
starting late Monday.

&&

Near term /until 6 am Thursday morning/...
instead of welcoming Spring, we are welcoming back winter across
the tri-state area as chilly air has returned in the wake of a
cold front that passed across the area this morning. The main
impact in the wake of this front has been gusty northwest winds
especially from the city east across Long Island and across CT.
Gusts have even exceeded 50 mph in a few land based locations
including a 54 mph gust at the Westhampton Airport. Wind
advisories will be left up as is with coastal areas hanging onto
them longer. Surface pressure gradients remain up through most
of the night, however, the WRF keeps 925 mb winds over 35 kts
across much of the area through 06z Thursday. There is a bump in
the 925 mb winds on this model between 03z and 06z across
Fairfield County extending into Queens, Nassau and western
Suffolk counties, so there is a possibility if some of this
higher momentum aloft mixes down of the need to extend wind
advisories in some areas for a few hours.

Even though winds will gradually drop off overnight in
strength, we should still see enough of a breeze overnight to
prevent a full decoupling. Thus did not do two much tweaking of
lows in the normal radiational spots though we still show
between 3 and 5 inches of snow on the ground in the Hudson
Valley in Orange and Putnam counties as of this morning. A
clear sky is expected tonight with lows around 20 in the city
and most other areas in the teens. The coldest spots will be
close to 10 well inland. Some record lows may get reached or
tied tonight, see the climate section below.

&&

Short term /6 am Thursday morning through 6 PM Thursday/...
surface high pressure will slide southeast from the Great Lakes
Thursday morning toward the Delmarva Peninsula by Thursday
afternoon. This will result in a clear sky with northwest winds
shutting off by the late morning and winds turning to the west
to southwest by the afternoon which will push readings back to
near 40 in the city with lower 40s in urban sections of
northeastern New Jersey and the 30s elsewhere. Ample sunshine will help
take the edge off the early Spring chill.

&&

Long term /Thursday night through Wednesday/...

The good news is the really cold weather is on the way out,
however, so is seeing the sun during much of the extended as an
unsettled weather pattern sets up.

A warm front will lift north across the area Thursday night into
Friday morning in advance of an area of low pressure ejecting
out of the Southern Plains. As the plains low gets closer
an increase in moisture will take place and spread light
precipitation into the area on Friday morning - possibly as
early as 5 to 8 am. Given temps will be near to below freezing
especially inland in the normal Klondike spots of Orange,
Putnam, Passaic and CT, there will be the risk for frozen
precipitation before temperatures gradually rise above freezing
with the passage of the warm front. Forecast model soundings all
show a warm nose or warm layer aloft with shallow cold air so
the risk for a variety of frozen precipitation exists. Across
north Jersey and the lower Hudson Valley, frozen precipitation
may start as snow but quickly go to sleet or more likely
freezing rain as the warm layer aloft surges in. Model soundings
look a little better for a bit more in the way of snow across
interior CT, where at Danbury snow may last a little longer
before mixing with sleet and/or freezing rain for a bit before
transitioning to all rain. Either way, quantitative precipitation forecast amounts are mainly a
tenth of an inch or less so this will not be a big event but
perhaps just enough to create some slick spots on roads if it
lasts long enough. If precip is slower to arrive, then p-type
will be more likely just rain as temps will warm up by later in
the morning. However, this short lived cold snap will chill any
Road surfaces allowing for even a light amount of precip to get
slick except in spots where a hefty salt still sits on the
roads.

By Friday night, the warm front should push far enough north
that most of area dries out except for inland CT where some
light rain may linger.

The Southern Plains low advances east on Saturday toward St.
Louis. Our area should be in the warm sector, though still see a
decent amount of clouds. Depending on if we get any sun, temps
may crack 60 especially from the city on west. Southerly flow
off the chilly waters will hold Max temps down on the island,
CT and southern parts of Brooklyn and Queens into the 50s.

The warm front to our north will start to get shoved back south
by later in the day in response to a surface high pressure over
eastern Canada. Model consensus is there as to a backdoor cold
front moving toward the area Saturday evening and thus we showed
an increase up in pops in that time frame from east to west
across CT and Long Island. Also given the marine push, I added
in patchy fog as we may end up seeing more drizzle at times than
actual light rain. Temps will slowly fall through the night.
Inland we may see a little frozen precipitation if colder air
seeps in better than expected.

Sunday the main issue is where does the front stall out. The
European model (ecmwf) on the 00z operational run was warmer by about 10 degrees
in spots than the 12z operational GFS. For now I played temps
in between but suspect from the city on east the cooler scenario
will win on out but there is certainly some bust potential with
temps. In many spots readings may hold steady or even fall
through the day depending on what the front decides to do. We
kept in a chance of rain through the day as the approaching low
from the west and the front overhead should keep enough lift in
place to keep things wet most of the time.

Beyond Sunday waves of low pressure are expected to impact the
area with a frontal boundary near or north of the area. The
first wave should pull east by Monday morning but model
agreement was poor after this with timing and the track of the
lows. Given the pattern, frozen precipitation may be possible at
times well inland especially at night where any cold air is
trapped. If the frontal boundary hangs up further south then
frozen precipitation is possible further toward the coast. Most
likely though the flow aloft is west to southwest, so I have
favored a warmer forecast. I bumped up temps a bit over the
previous forecast based on a blend of the operational GFS and
European model (ecmwf). There could be some breaks in rain at times, but this far
out exact timing of features is difficult.

&&

Aviation /19z Wednesday through Monday/...
VFR through the taf period with mainly clear sky.

Northwest winds near 25kt with gusts up to 40kt peaking this afternoon.
Gusts begin to drop off toward sunset and diminish after
midnight. Winds pick up again for a few hours midday Thursday
but likely drop off in the early afternoon as high pressure
settles across the area.



New York Metro enhanced aviation weather support...

Detailed information, including hourly taf wind component forecasts,
can be found at: http:/www.Weather.Gov/zny/n90

Kjfk taf comments: no unscheduled amendments expected.

Klga taf comments: no unscheduled amendments expected.

Kewr taf comments: no unscheduled amendments expected.

Kteb taf comments: no unscheduled amendments expected.

Khpn taf comments: no unscheduled amendments expected.

Kisp taf comments: no unscheduled amendments expected.

Outlook for 18z Thursday through Monday...
18z Thursday..VFR. Northwest winds becoming SW-west 10-15 knots.
Friday...MVFR possible. Chance of rain showers. SW gusts 25 kt.
Saturday...mainly VFR. Chance of mid-late afternoon MVFR in
cigs and -shra.
Saturday night and Sunday...MVFR/IFR and rain. East-southeast gusts
20-25 kt.
Monday...MVFR possible in showers.

&&

Marine...
gusty winds of 35 kts+ and waves of 4 to 7 ft will continue
through early this evening before conditions start to decrease
tonight from west to east. Gale Warning remains until 06z
Thursday. Small Craft Advisory remains likely thereafter late tonight into early
Thursday before all waters go below Small Craft Advisory for the rest of
Thursday. Freezing spray was kept in for later tonight into
Friday morning especially for the ocean waters and eastern end
of the sound.

High pressure moves across the waters Thursday night, and passes
well to the east Friday. Winds diminish during this time, but begin
to increase from the SW later Friday into Friday night.

A cold front approaches from the north Saturday, and settles near or
just south of the waters Saturday night into Sunday. Winds diminish,
and turn toward the E/NE. Speeds increase yet again Sunday as high
pressure builds well to the north.

&&

Fire weather...
northwest winds of 15-30 mph with gusts 35-50 mph and min relative humidity dropping
to near 20 to 25 percent should help dry fine fuels in areas
where the snowpack is gone. This will enhance the threat for
brush fire spread in those areas through this evening. Winds
are lighter but similar relative humidity values are expected for Thursday.

&&

Hydrology...
unsettled weather from this weekend through early next week may
result in an inch or more of precipitation. However, this would
occur over a prolonged period and would be intermittent, so no
hydrologic concerns are anticipated. Snowpack melt in interior
sections will continue at a slow rate through Thursday with
most areas likely loosing any significant snowpack by Saturday
as temperatures rise to above normal readings and lows even
remain above freezing.

&&

Climate...
the following are record low temperatures for Thursday March
23, 2017 along with the forecast low temperatures.

Record low temperature forecast low temperature
---------------------- ------------------------
Central Park........12 (1875) 21
LaGuardia...........20 (1959) 22
Kennedy.............20 (1959) 21
Islip...............15 (2004) 18
Newark..............13 (1934) 19
Bridgeport..........19 (2004) 19

&&

Okx watches/warnings/advisories...
CT...Wind Advisory until 6 PM EDT this evening for ctz005>012.
New York...Wind Advisory until 8 PM EDT this evening for nyz072>075-
078>081-176>179.
Wind Advisory until 6 PM EDT this evening for nyz067>071.
New Jersey...Wind Advisory until 6 PM EDT this evening for njz002-004-006-
103>108.
Marine...Gale Warning until 2 am EDT Thursday for anz330-335-338-340-
345-350-353-355.

&&

$$
Synopsis...cs
near term...cs
short term...cs
long term...pw/cs

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