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fxus61 kokx 280911 
afdokx

Area forecast discussion
National Weather Service New York New York
511 am EDT Wed Jun 28 2017

Synopsis...
high pressure builds into the region today, and offshore on
Thursday. A warm front moves north of the region Thursday
night. Bermuda high pressure then dominates Friday into
Saturday before a cold front moves through Sunday into Sunday
night. The front may then linger just south of the region early
next week.

&&

Near term /through tonight/...
low dewpoint depressions this mrng due to radiational cooling.
There have been some pockets of fog, particularly across CT.
Patchy fog is expected until sunrise, when any of the shallow
fog should quickly dissipate.

A 1023 high was centered over WV at 7z. The high will drift ewd
thru tngt producing mainly clear skies and temps slightly blw
average. As temps approach convective this aftn, some flat cu
around 6000 ft is possible.

&&

Short term /Thursday/...
as the high drifts ewd over the Atlantic, the winds will begin
to respond to lowering pres over srn Ontario. This flow, coupled
with the sea breeze circulation, should produce windy conditions
along the coasts by late in the day. Otherwise, all other areas
should have a sly breeze at least. The latest modeling from the
NAM, GFS and European model (ecmwf) keeps any frontal systems N of the cwa, so
pcpn has been removed from the fcst. Humidity will increase due
to the increasing flow off the ocean, and temps will warm to aoa
average as a thermal ridge begins to build in. The 00z models
have around 14-16c at h85 by the end of the day. If things
unfold as currently expected, dangerous rip currents will be
possible, particularly in the late aftn and eve, requiring a
high risk fcst.

&&

Long term /Thursday night through Tuesday/...
the main trend in the long term is for warmer and more humid
conditions to take shape over the tri-state.

On the larger scale, a shortwave passes to the north Thursday night
followed by rising heights and western Atlantic ridging taking shape
Friday into Saturday. This ridge axis moves offshore Sunday as the
next shortwave trough moves across New England through Sunday night.
Another shortwave trough may follow early next week. Models and
ensembles are in good agreement overall on the large scale through
the weekend, then diverge a bit with the handling of any shortwaves
early next week.

At the surface, a warm front moves north of the region Thursday
night. Bermuda high pressure will then influence the weather Friday
into Saturday before a cold front moves through Sunday into Sunday
night. There may be weak surface trough development to the northwest of NYC
each day before the cold front moves through Sunday. This front may
then linger to the south early next week.

Shower and thunderstorm chances appear slim Thursday night and
mainly to the north and west of NYC. The same holds true on Friday
into Saturday as ridging and heights build aloft. The best chance of
any convection is mainly from the city north and west. Shower/storm
chances increase a bit across the entire area on Sunday with the
passage of the cold front and approaching shortwave. Drier
conditions return on Monday with the next chance at showers and
storms on Tuesday.

Temperatures Friday and Saturday will be in the upper 80s with
increasing humidity levels. A few 90 degree readings are also
possible in the NYC Metro and NE New Jersey. Max heat indices look to stay
in the lower 90s both days at this time at these locations, with
upper 80s elsewhere. Closer to the coast, onshore flow will keep
highs in the lower to middle 80s. Temperatures should be a bit
cooler on Sunday in the lower and middle 80s due to increasing
clouds and higher coverage of showers/storms. Highs should gradually
fall back closer to normal early next week.

&&

Aviation /09z Wednesday through Sunday/...
high pressure builds into the region through today. Some patchy
fog is forecast outside of city terminals into daybreak with
brief MVFR/IFR vsbys.

Otherwise, VFR through the taf period. West-northwest winds under 10 kt
eventually back to SW this afternoon, increasing 10-15 kt with
gusts up to 20 kt for most terminals. Winds subside to a S-SW
flow near 10 kt or less tonight.

..NY Metro enhanced aviation weather support...

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

Kjfk taf comments: high confidence in category forecast.
Moderate confidence in wind forecast. More SW-S flow could
arrive 1-2 hours earlier than forecast. Gust timing could be
1-2 hours off from forecast.

Klga taf comments: high confidence in category forecast.
Moderate confidence in wind forecast. More SW-S flow could
arrive 1-2 hours earlier than forecast. Gust timing could be
1-2 hours off from forecast.

Kewr taf comments: high confidence in category forecast.
Moderate confidence in wind forecast. More SW-S flow could
arrive 1-2 hours earlier than forecast. Gust timing could be
1-2 hours off from forecast.

The kewr afternoon haze potential forecast is green, which implies
slant range visibility more than 6sm outside of cloud.

Kteb taf comments: high confidence in category forecast.
Moderate confidence in wind forecast. Gust timing could be 1-2
hours off from forecast.

Khpn taf comments: high confidence in category forecast.
Moderate confidence in wind forecast. More SW-S flow could
arrive 1-2 hours earlier than forecast. Gust timing could be
1-2 hours off from forecast.

Kisp taf comments: low confidence in category forecast early
this morning. VFR could last through 11z. Higher confidence of
VFR after 11z. Moderate confidence in wind forecast. More SW-S
flow could arrive 2-4 hours earlier than forecast.

Outlook for 09z Thursday through Sunday...
Thursday...mainly VFR. SW g20-25kt aftn/evening. Slight chance
of an shower/thunderstorm at night.
Friday...mainly VFR. SW g20kt late morning through the evening.
Chance of shra/tstm, mainly for the afternoon into early
evening.
Saturday...mainly VFR. SW g20kt aftn/evening. Chance of
shra/tstm mainly for the afternoon and night
Sunday...mainly VFR. Chance of shra/tstm.

&&

Marine...
winds and seas will remain below sca levels thru tngt. Sly
winds will then increase on Thu, with sca cond possible by aftn.
Strong SW flow continues on the waters Thursday night into
Friday, with Small Craft Advisory conditions likely on the ocean. Gusts will be
highest Thursday night, 25-30 kt and then closer to 25 kt on
Friday. Ocean seas will be 5-7 ft Thursday night, subsiding to
around 5 ft late Friday. 5 ft seas may linger into Friday night.
A weaker pressure gradient is expected this weekend leading to
sub-sca conditions on all waters.

&&

Hydrology...
no hydrologic impacts expected through the beginning of next
week.

&&

Equipment...
observations from kfrg (farmingdale, ny) may be sporadic.
Observations from khpn (white plains ny) and khvn (new Haven
ct) are being disseminated through backup methods. All is due to
an FAA communication line outage. Return to full service time
is unknown.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...none.

&&

$$
Synopsis...jmc/ds
near term...jmc
short term...jmc
long term...ds

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