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fxus61 kokx 190756 
afdokx

Area forecast discussion
National Weather Service New York New York
356 am EDT Fri Jul 19 2019

Synopsis...
a warm front moves through today bringing a return to hot
conditions. High pressure then remains dominant over the
southeastern states into the weekend. A cold front approaches
and moves across the region Sunday night through through Monday.
High pressure returns Tuesday and remains through Thursday.

&&

Near term /through tonight/...
the lingering remnants of T.C. Barry and an attendant surface
low will quickly pass to the east this morning, with any
lingering showers coming to an end. The inversion that held
overnight due to colder surface air associated with high
pressure to the north will rapidly erode as a warm front moves
through, allowing stratus to clear and bringing a return to
west- southwest flow and well above normal temperatures to the
area. Today will mark the start of a heat wave for the region
that is expected to peak this weekend. The interior areas of
northeastern New Jersey, NYC, into the lower Hudson Valley will
likely record temperatures solidly in the 90s, to near 95.
Elsewhere, both deterministic and hi resolution data have
trended more towards onshore flow, particularly for Long Island
and portions of coastal Connecticut, though unusually high dew
points remain, and will lead to higher heat indices despite the
cooler temperatures relative to areas to the west. Heat
headlines look good at the moment, though it's possible that
coastal southeastern Connecticut and the Twin Forks of Long
Island may fall just short of heat advisory levels.

Outside of heat headlines, potential for thunderstorms will be a
concern. Early this morning, an mesoscale convective system is moving through the Great
Lakes region, and is expected to continue eastward. This
convectively induced vorticity maximum will reach our area by
evening. Several runs now of hi resolution data, as well as
some 00z deterministic models now indicate that convective
coverage will increase upstream, with outflow boundaries
initiating new activity, developing into clusters as they move
into our area. Similar to the past few days, high precipitable
water should lead to precip loading, with any downdrafts then
enhanced in the dry subcloud layer. Strong to perhaps severe
winds and heavy rainfall will be possible. These storms should
then gradually diminish with eastward extent with the loss of
diurnal heating and as they move into the marine layer.

Overnight lows will continue to be well above normal, with some
record high minimum values possible.

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

&&

Short term /Saturday through Sunday/...
the forecast area will remain between a building Bermuda high
and an upper trough centered around the Hudson Bay to the north,
with strengthening westerlies between the two systems. With
little onshore component and at least some downslope flow,
temperature values will feel oppressive when combined with
ongoing high dew points and humidity. The heat wave is expected
to peak this weekend, with several temperature records possibly
in jeopardy.

An excessive heat warning remains in effect, as heat indices
will largely be in excess of 105 for the entire area, with the
exception of the Twin Forks of Long Island, which may have more
of an onshore component. Utilized a blend for forecast
temperatures with higher resolution data, as temperature
differences may be large across small areas, most notably across
Long Island where the South Shore with an ocean breeze may be
around 10 degrees cooler than the North Shore. Anomalously high
dew points will remain, and low temperatures will remain
oppressive. Of note, Sunday may now be the hottest of the two
days for many locations.

Apart from heat, weak height falls begin late Sunday as the
ridge shifts slightly east ahead of the approaching upper
trough. Although there will be no strong feature to initiate
thunderstorms, the weak height falls combined with a thermal
trough and sea breezes may be sufficient enough to trigger
convective activity. Expect gusty winds and heavy rainfall with
any storms that can develop.

There is a moderate rip current risk at the ocean beaches for
Saturday.

&&

Long term /Sunday night through Thursday/...
a cold front will approach the region Sunday night into Monday,
pushing across the region during the second half of Monday and
Monday night. This will mark the end of the high heat and humidity
which will have been in place through the weekend. Expect
precipitation (showers and thunderstorms) chances to increase Sunday
night and Monday, with the best chances Monday afternoon. The front
seems to stall offshore on Monday night into Tuesday, which should
result in some additional lingering showers and thunderstorms. High
pressure will gradually build into the area from the west, with dry
weather expected for the middle of the week.

Max temperatures in the long term will climb into the 80s Monday
through Thursday. Much lower humidity levels will finally be felt on
Tuesday as dew points finally fall back into the 50s and lower
60s.

&&

Aviation /06z Friday through Tuesday/...
a cold front will dissipate south of the region into this morning. A
Bermuda high will be in place today through tonight.

MVFR/IFR stratus over the terminals will eventually scatter out this
morning, 11-13z. Mainly VFR conditions are then expected for the
remainder of the taf period. Only exception would be brief MVFR/IFR
in any showers or thunderstorms, which there will be a chance of
near kswf this evening.

Winds initially around 5kt generally out of the N-NE. The winds
become S-SW 5-10 kt late this morning into the early this afternoon
and then further increase to around 15kt with gusts up to 20 kt for
some terminals, mainly near NYC. Winds decrease in the evening with
gusts diminishing.

..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: amendments possible for changing flight
categories into this morning which could vary between MVFR and IFR.

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

Klga taf comments: amendments possible for changing flight
categories into this morning which could vary between MVFR and IFR.

The afternoon klga haze potential forecast is yellow, which implies
slant range visibility 4-6sm outside of cloud.

Kewr taf comments: amendments possible for changing flight
categories into this morning which could vary between MVFR and IFR.

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

Kteb taf comments: amendments possible for changing flight
categories into this morning which could vary between MVFR and IFR.

Khpn taf comments: amendments possible for changing flight
categories into this morning which could vary between MVFR and LIFR.

Kisp taf comments: amendments possible for changing flight
categories into this morning which could vary between MVFR and LIFR.

Outlook for 06z Saturday through Tuesday...
late tonight through Saturday night...mainly VFR.
Sunday...chance of showers and tstms starting in the afternoon
with MVFR or lower possible.
Sunday night through Tuesday...chance of showers/tstms with MVFR or
lower possible.

&&

Marine...
S-SW winds on the ocean waters in the afternoon will push 15 to
20 kt and then weaken tonight. A brief period of 5 ft seas on
the ocean will be possible by tonight, though confidence is too
low to issue an advisory at this time. Seas then subside briefly
into the weekend with flow becoming more westerly.

Thereafter, southerly flow returns for Sunday night, and may
allow waves on the ocean to build to 5 ft through Tuesday,
mainly for the central and eastern ocean zone.

&&

Hydrology...
no widespread hydrologic impacts are expected into next week.

&&

Climate...
the following are records for this weekend:

Record highest minimum temperatures for Saturday, July 20:

Nyc: 82 in 2015
lga: 83 in 2015
jfk: 79 in 2015
ewr: 80 in 2015
isp: 78 in 2013
bdr: 79 in 2013

Record high temperatures for Saturday, July 20:

Nyc: 101 in 1980
lga: 101 in 1991
jfk: 96 in 2013 (also occurred in previous years)
ewr: 101 in 1980
isp: 97 in 1991
bdr: 95 in 1001

Record highest minimum temperatures for Sunday, July 21:

Nyc: 82 in 1980
lga: 83 in 1980
jfk: 79 in 2017
ewr: 81 in 1980
isp: 76 in 1980
bdr: 76 in 1994

Record high temperatures for Sunday, July 21:

Nyc: 104 in 1977
lga: 100 in 1991
jfk: 99 in 1991
ewr: 103 in 2011
isp: 101 in 1991
bdr: 98 in 1991

&&

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

&&

Okx watches/warnings/advisories...
CT...excessive heat warning from 6 am Saturday to 8 PM EDT Sunday
for ctz005>012.
Heat advisory from noon today to 6 am EDT Saturday for
ctz005>012.
New York...excessive heat warning from 6 am Saturday to 8 PM EDT Sunday
for nyz078>081-177-179.
Heat advisory from noon today to 6 am EDT Saturday for
nyz078>081-177-179.
Excessive heat warning from noon today to 8 PM EDT Sunday for
nyz067>075-176-178.
New Jersey...excessive heat warning from noon today to 8 PM EDT Sunday for
njz002-004-006-103>108.
Marine...none.

&&

$$
Synopsis...BC/MD
near term...Maryland
short term...Maryland
long term...British Columbia
aviation...jm

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