Area forecast discussion
National Weather Service New York New York
956 am EDT Wednesday Jun 19 2013
Synopsis...
high pressure builds in from the northwest today and remains in
control through the end of the week. A weak cold front will pass
through the area Sunday night into Monday with high pressure
returning in its wake.
&&
Near term /until 6 PM this evening/...
forecast on track this morning. Updated temperatures/dew points for current
trends. Also decreased sky cover has clouds have cleared out over
the last few hours as drier air and high pressure builds in from
the west.
Otherwise...high pressure builds in at the surface. Aloft...a trough
axis and shortwave will be passing through...but with little
consequence. Mostly sunny with a dry airmass as surface dewpoints
drop into the 40s this afternoon. Mixing profiles support highs of
mostly 75-80.
There is a moderate risk of rip currents at Atlantic Ocean beaches
today.
&&
Short term /6 PM this evening through Thursday night/...
light to calm winds and a mostly clear sky tonight will allow for
decent radiational cooling outside of the city...with lows 5-10
degrees below normal in most of the suburbs.
High pressure center shifts offshore on Thursday with a return SW-S
flow setting up. Sea breezes are likely as winds remain light
through the first few thousand feet in elevation. Surface dew points
should remain at comfortable levels in spite of this as drier air
from aloft mixes down. Mixing won't be as deep as today due to
subsidence...however temperatures at the top of the mixed layer
should allow for highs of generally 75-80 once again.
Dry weather continues into Thursday night with lows still below
normal...but not as cool as tonight.
&&
Long term /Friday through Tuesday/...
global models in good agreement with the overall pattern in the long
term time frame. Aloft...a mean trough will give way to slightly
rising heights by Saturday and continuing to build through the week.
GFS is slightly more aggressive with the strong ridge moving in
while the European model (ecmwf) tracks a shortwave through Monday and then quickly
rises The Heights.
At the surface... high pressure remains in control through the long
term with a general south-southwest flow. Used a mav/met blend for
temperatures on Friday with a good general agreement for near normal
values. Temperatures will continue to moderate through the week and used
wpc guidance as it seemed reasonable with no major temperature
fluxes. Near to just above normal temperatures are expected.
Models trying to hint at a few showers on Friday but have continued
the dry forecast with little instability or lift. On Saturday...a
cold front will weaken and dissipate by the time it reaches the
western County Warning Area boundary. With some instability in place with afternoon
heating...this boundary could create a few showers...mostly in far
north and west zones. Have left chance probability of precipitation for that area.
Highest chances for showers and thunderstorms will be Sunday night
into Monday as a cold front approaches and possibly remaining
stationary through Monday. European model (ecmwf) also trying to hint at a potential
decaying mesoscale convective system tracking southeast along the front...along the southern side
of an upper jet. Will generally keep chance probability of precipitation in the areas north
and west of NYC and slight chance elsewhere. The northern areas will
have the highest instability during the day and therefore the
greatest precipitation chances.
&&
Aviation /14z Wednesday through Sunday/...
high pressure builds in from the Great Lakes through tonight.
VFR through the taf period. Middle and high clouds gradually
dissipate through the day...then sky clear tonight.
North-north-northeast around 10 knots through at least early afternoon with isolated
gusts 15-20 knots...except at kewr which likely will have more
frequent gusts from midday into early afternoon. Sea breeze likely
middle-late afternoon/early evening kbdr/kgon/kjfk/kisp/klga/kewr.
Winds become light and variable at all terminals this evening.
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: moderate-high confidence in seabreeze - low
confidence in exact timing. Could be off +/- 2 hours. Isolated
gusts to 15-20 knots possible through early afternoon. High
confidence in winds to the right of 300 true through early
afternoon.
Klga fcster comments: moderate confidence in seabreeze - low
confidence in exact timing. Could be off +/- 2-3 hours. Isolated
gusts to 15-20 knots possible through early afternoon. High
confidence in winds to the right of 300 true through early
afternoon.
Kewr fcster comments: moderate confidence in seabreeze - low
confidence in exact timing. Could be off +/- 2-3 hours. Isolated
gusts to 15-20 knots possible through midday...then moderate
confidence in more frequent gusts around 16-20z. High confidence
in winds to the right of 300 true through early afternoon.
The afternoon kewr haze potential forecast is green...which
implies slant range visibility 7sm or greater outside of cloud.
Kteb fcster comments: low-moderate confidence in seabreeze - low
confidence in exact timing. Could be off +/- 2-3 hours. Isolated
gusts to 15-20 knots possible through early afternoon.
Khpn fcster comments: very low chance of seabreeze late this
afternoon/early this evening. Isolated gusts to 15-20 knots
possible through early afternoon.
Kisp fcster comments: moderate-high confidence in seabreeze - low
confidence in exact timing. Could be off +/- 2 hours. Isolated
gusts to 15-20 knots possible through early afternoon.
Outlook for 12z Thursday through Sunday...
Thursday-Saturday morning...VFR.
Saturday afternoon/night. Mainly VFR...except MVFR or lower
possible in isolated-scattered rain showers/thunderstorms and rain mainly to the north/west of city
terminals in the afternoon/evening.
Sunday...MVFR or lower possible.
&&
Marine...
high pressure builds in over the waters through the day today.
With cold air advection and a relatively tighter pressure
gradient...the eastern ocean waters may occasionally gust up to 25
knots during the earlier morning hours. Otherwise...a northerly flow at
around 15 knots weakens this afternoon with local sea breeze directions
developing nearshore late in the day. A light return S to SW flow
develops for Thursday as the center of high pressure shifts
offshore. Tranquil conditions therefore prevail.
Winds and seas are expected to remain below Small Craft Advisory criteria through
early next week as high pressure remains over the area.
&&
Hydrology...
dry weather is expected through at least Sunday morning. Showers and
thunderstorms are possible each afternoon sun-Tuesday but no
widespread significant precipitation is expected.
&&
Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...none.
&&
$$
Synopsis...jc/ln
near term...ds
short term...jc
long term...line
aviation...maloit
marine...jc/ln
hydrology...jc/ln
