159
FXUS61 KOKX 200915
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
515 AM EDT Fri Jun 20 2025
.SYNOPSIS...
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Low pressure will move across northern New England and eastern
Canada today as high pressure builds to the south, while a
weakening disturbance approaches from the northwest late today.
A warm front will pass to the north this weekend as the high
becomes established off the Mid Atlantic and Southeast coasts.
The high will remain in place early to mid next week. A frontal
system may impact the area late next week.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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Cold front moving into ern Long Island/SE CT with winds shifting
NW and gusting to 25-30 kt. Gusts up to 25 should continue
through much of the day today as winds become more westerly
after passage of an upper trough. Skies should be mostly sunny,
then a trailing shortwave trough may generate sct showers/tstms
from NYC north/west late today. Temps should reach the lower and
mid 80s in most places.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
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Ongoing sct convection in the late day hours should wane after
sunset. Expect partly to mostly cloudy skies tonight especially
inland as cloud debris from an upstream MCS overspreads the
area.
Fcst for daytime Sat is dry, with expectation that another
upstream MCS should pass to the north along a warm front late
day Sat into Sat night, but this will have to be watched as it
could skirt areas from NYC north/west per SPC Day 2 Outlook
which carries a marginal svr risk. Temps should be a little
warmer, near 90 in NYC and NE NJ and in the mid/upper 80s
elsewhere.
Another MCS should traverse ern CT on Sunday. As mentioned in
the SPC Day 3 outlook, guidance varies substantially regarding
the strength/timing of the shortwave trough moving across New
England Sunday morning, and there is some potential for isolated
strong tstms. A slower system could result in a more robust
diurnal threat, while a faster system may confine the primary
threat to the morning. Attm have confined this threat to SE CT
mainly for the morning hours.
Meanwhile, high heat and increasing humidity should commence on
Sunday. H8 temps reaching 21-22C (at least in urban NE NJ) with
a downslope W flow supports GFS MOS idea of high temps reaching
100 in urban NE NJ, the upper 90s in surrounding areas
including NYC, and the lower/mid 90s elsewhere to the
north/east. A blend of the NBM and its 90th percentile is also
close to these values; NBM 90th percentile has more widespread
100+ temps inland as well as higher temps into eastern CT, but
did not go with these higher numbers as any convection could
limit temps especially across SE CT. Heat index values as
dewpoints increase should be a few degrees higher, with 105
possible in urban NE NJ, 100-104 for the NYC metro area and
parts of the Hudson Valley/SW CT, and mid/upper 90s most
elsewhere except for coastal SE SE and the south shore/forks of
Long Island.-- End Changed Discussion --
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
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Key Messages:
* Increasing confidence in hot and humid conditions early next
week.
Global guidance continues to show a shift in the pattern as a
large sprawling high pressure system develops to the south
early next week. This will result in dry and mostly clear
conditions under a light SW flow. This will advect moisture into
the area so that dewpoints rise into the upper 60s to low 70s
through early to mid next week. As a vertically stacked ridge
develops, height rises allow the middle and lower atmosphere to
warm such that 500 mb heights of 597 dm are positioned over the
area by Monday and Tuesday.
Ample surface heating will provide for the lower BL to mix down
these warmer temperatures with surface temperatures expected to
climb into the middle 90s to possible near 100 for some
locations Monday and Tuesday. The immediate coast may rise into
the low to mid 90s as well, with a generally W-SW flow
preventing the ocean from cooling the air mass much. Given the
high dew points coinciding with the heat, heat index values for
interior portions of the area may exceed 100 degrees for
several days. Closer to the coast, heat index values in excess
of 95 degrees remain possible. The peak of the heat will be on
Monday and Tuesday.
By Wednesday, heights begin to fall a bit as the ridge slowly
weakens, giving way to more mid-level energy approaching from
the north. This may also result in the development of afternoon
showers and thunderstorms Wednesday and Thursday as the heat
gradually falls off. Highs on Wednesday will still be above
average, generally in the upper 80s to mid 90s. By Thursday,
highs return to near normal with temperatures in the low to
mid 80s. A frontal system may develop and impact the area late
in the week as well.-- End Changed Discussion --
&&
.AVIATION /09Z FRIDAY THROUGH TUESDAY/...
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A cold front is moving across the terminals early this morning.
Western Atlantic high pressure then builds into Friday.
Mainly VFR conditions through the TAF period though some
terminals may go briefly MVFR due to residual low cigs through
morning.
Winds are gradually becoming more W/WNW this morning at 10-15 kt
with gusts upwards of 20-25 kt behind the cold frontal passage.
This westerly flow and gusts should persist through the day.
Gusts expected to fall off after 22Z, but may linger a few hours
into the evening, especially for the NYC metro.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Brief MVFR is possible this morning in lingering low cigs.
.OUTLOOK FOR 09Z SATURDAY THROUGH TUESDAY...
Friday night: VFR.
Saturday through Tuesday: Mainly VFR. SW wind gusts 15-20 kt for
Sunday.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
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SCA issued for NY Harbor and the Long Island south shore bays
until 8 AM as winds gust up to 25 kt following a cold frontal
passage. The advy there may need to be extended in time into at
least part of today, and possibly in area to include the western
Sound, as W flow with gusts up to 25 continue through much of
the day over adjacent land areas and could impact the near shore
waters. On the ocean, seas 4-6 ft should continue through the
morning on all waters, then E of Fire Island Inlet this
afternoon/evening.-- End Changed Discussion --
&&
.HYDROLOGY...
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There are no hydrologic concerns attm.-- End Changed Discussion --
&&
.TIDES/COASTAL FLOODING...
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The rip current risk today is moderate with lingering 4-5 ft
seas on a 7s wave period. The risk may end up increasing to high
for the Suffolk beaches if seas are slightly higher than
expected.
Saturday looks more marginal, with diminishing swell.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 8 AM EDT this morning for ANZ338-
345.
Small Craft Advisory until 11 PM EDT this evening for ANZ350.
Small Craft Advisory until 6 PM EDT this evening for ANZ353.
Small Craft Advisory until noon EDT today for ANZ355.-- End Changed Discussion --
&&
$$
SYNOPSIS...BG/MW
NEAR TERM...BG
SHORT TERM...BG
LONG TERM...MW
AVIATION...MW
MARINE...BG/MW
HYDROLOGY...BG/MW
TIDES/COASTAL FLOODING...BG