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fxus61 kokx 230820 cca 
afdokx

Area forecast discussion...corrected
National Weather Service New York New York
420 am EDT Mon Sep 23 2019

Synopsis...
a cold front approaches today and passes through tonight. High
pressure then slowly begins to build in Tuesday night. High
pressure during the second half of the week will briefly be
interrupted by a fast moving cold front on Thursday. Another
cold front will then settle southward across the region Saturday
night into Sunday.

&&

Near term /until 6 PM this evening/...
closed 500mb low tracks near the northern Great Lakes and
strengthens a surface low to its east. An associated cold front and
pre-frontal trough approach the tri-state area. There could be
showers and possibly even a thunderstorm north and west of the city this
afternoon with the pre-frontal trough.

High temperatures will be above normal across the area. 850mb temps
are forecast to be about a degree warmer than yesterday's, but there
will probably be at least a little more in the way of clouds this
time around. Expecting highs within a degree or two of yesterday's,
with parts of NYC and NE New Jersey near 90, and 80s for most other areas.
This is 10-15 degrees warmer than normal, but not expecting any
record high temperatures to be challenged.

There is a high rip current risk at the ocean beaches today.

&&

Short term /6 PM this evening through 6 PM Tuesday/...
the strongest overall lift arrives this evening with the passage of
the cold front combining with some lift from aloft. This setup
will bring the best chances of rainfall, and there will still be
a chance of a thunderstorm with some cape available. Rain
chances then diminish west to east overnight with the departing
cold front.

The cold front moves farther offshore on Tuesday, but high pressure
will be slow to build in its wake as the trough axis associated with
the upper low to our north shifts through here. The cyclonic flow
and some moisture streaming in from the northwest will promote some
afternoon cumulus development. 850mb temps cool down to 9-10c, and
with a downsloping flow, highs in the upper 70s for the city, Li,
and NE New Jersey. Lower and mid 70s expected elsewhere.

There is a high rip current risk at the ocean beaches for
Tuesday.

&&

Long term /Tuesday night through Sunday/...
a fairly progressive upper flow will be featured during the
period with the westerlies active across the northern third of
the country. This will result in another cold frontal passage on
Thursday, with surface high pressure generally in control from
Wednesday through Saturday.

Global models then point toward a pattern change the following
week with anomalously warm heights across the eastern U.S. As a
highly meridional flow sets up. The greatest uncertainty lies in a
potential cold frontal passage late Saturday into Sunday as a
strongly confluent mid level flow sets up across eastern Canada
and the northeast. The latter of which will increase surface
pressures as a high attempts to build in from the north. The
combination of the building heights and confluent flow lend to
the question just how far south will the boundary be able to get.
The operational GFS is on the faster side on the model envelope.
Preference at this time was to go closer to the slower European model (ecmwf) and
ggem. Regardless, a 6-12 hour difference at this juncture in time
is negligible.

Rain chances are limited during the period with low probabilities
with each cold frontal passage as lift, moisture, and instability
are all marginal.

As for temperatures, generally remain above normal through the
period with the largest departures ahead of the cold fronts.
Thus, Thursday and Saturday look to be the warmest days of the
period with the best chance of eclipsing the 80-degree mark.
Otherwise, highs will be in the 70s. Lows will generally be in
the 50s to around 60, but also warmer Thursday morning and
Saturday night ahead of the cold fronts.

&&

Aviation /08z Monday through Friday/...
high pressure offshore gives way to an approaching cold front, which
will move across tonight. Showers will accompany the front with a
chance for thunderstorms as well. Highest chances for showers are
this evening. Thunderstorm chances lower overnight. Outside of any
showers or thunderstorms, mainly VFR conditions are expected through
the taf period.

Regarding winds, much of the taf period will have S-SW flow. The
wind speeds will be 5-10 kts into early today. The winds then
increase to 10-15 kt late this morning into the afternoon and early
evening with some gusts to around 20 kt. Winds subside tonight and
become more westerly.



..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: timing of start and end time of gusts and showers
may vary 1-3 hours from forecast.

The afternoon kjfk haze potential forecast is green, which implies
slant range visibility p6sm outside of cloud.

Klga taf comments: timing of start and end time of gusts and showers
may vary 1-3 hours from forecast.

The afternoon klga haze potential forecast is green, which implies
slant range visibility p6sm outside of cloud.

Kewr taf comments: timing of start and end time of gusts and showers
may vary 1-3 hours from forecast.

The afternoon kewr haze potential forecast is green, which implies
slant range visibility p6sm outside of cloud.

Kteb taf comments: timing of start and end time of gusts and showers
may vary 1-3 hours from forecast.

Khpn taf comments: timing of start and end time of gusts and showers
may vary 1-3 hours from forecast.

Kisp taf comments: timing of start and end time of gusts and showers
may vary 1-3 hours from forecast.

Outlook for 06z Tuesday through Friday...
late tonight...MVFR possible in showers and possible thunderstorms.
Tuesday-Friday...mainly VFR. A low chance of showers Thursday.

&&

Marine...
SW flow increases through this afternoon ahead of an approaching
cold front. Small Craft Advisory conds expected on the ocean, and even occasional
gusts to 25 kt possible for the other waters. The cold front moves
through tonight, and an offshore flow for Tuesday remains below 25
kt. Seas during Tuesday on most of the ocean waters will
however remain elevated at advisory criteria due to an
increasing swell from Tropical Storm Jerry. Long period S-southeast
swells around 5 ft will then likely impact the ocean waters
through mid week. Additionally, a strengthening southerly flow
ahead of a cold front on Thursday will also contribute to these
seas with potential Small Craft Advisory conditions. See the Tropical Prediction
Center for forecasts on Jerry.

&&

Hydrology...
rainfall tonight will range mostly from a tenth to a third of an
inch with localized higher amounts possible. Any impacts are
more likely to be minor. Otherwise, no significant hydrologic
impacts expected through this week.

&&

Equipment...
NYC National oceanic and atmospheric administration weather radio station kwo35 (162.55 mhz) remains off
the air.

&&

Okx watches/warnings/advisories...
CT...none.
New York...high rip current risk through this evening for nyz075-080-081-
178-179.
New Jersey...none.
Marine...Small Craft Advisory until 6 am EDT Tuesday for anz355.
Small Craft Advisory until 6 PM EDT Tuesday for anz350-353.

&&

$$

Synopsis...jc/dw
near term...jc
short term...jc
long term...dw

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