Area Forecast Discussion
Issued by NWS Upton, NY-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KOKX 192005
Area Forecast Discussion
National Weather Service New York NY
305 PM EST Sun Feb 19 2017
Low pressure passes well to the north this afternoon as a weak
cold front north of the area dissipates. Another cold front
moves through the area tonight. High pressure then builds in
Monday before shifting offshore on Tuesday. A warm front will
approach Tuesday night followed by a weak cold front becoming
nearly stationary in our vicinity Wednesday through Friday. A
separate cold front approaches from the west Friday through
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A weak cold front into the Lower Hudson Valley and Massachusetts
was slowly weakening and is expected to dissipate as low
pressure tracks well to the north. A band of mid and high clouds
remains along the front with little movement. Winds did shift to
the northwest and temperatures along the coast have risen, with
a record set at Islip. See climate section below.
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
Stronger cold advection occurs tonight with a stronger cold front
moving through. Again, moisture is lacking so expect a dry passage.
For Monday, surface high pressure builds in with slow ridging aloft.
Sunny with cooler temperatures, but still above normal. MAV and NAM
MOS look too warm given temps at the top of the mixed layer, so went
with SuperBlend. Good radiational cooling conditions then set up for
late Monday night with a clear sky and light to calm winds as the
surface ridge axis shifts into the region.
.LONG TERM /TUESDAY THROUGH SUNDAY/...
High pressure ridge drifts offshore during Tuesday. Overrunning PCPN
ahead of a warm front to the west may sneak in by late over the
westernmost zones. Otherwise, expect increasing clouds with highs
near normal. CHC PoPs for Tuesday night as a warm front/cold front
combination approach the region. Good model agreement in that the
elevated warm layer will be warm enough for primarily rain, except
for a chance of sleet across the northern zones during the evening.
With clouds increasing and warm air advection with a lack of a cold
air damming pattern, thinking is that temps remain above freezing
through the night everywhere. Have therefore removed the chance of
freezing rain across the northern zones.
With the trailing cold front departing in the morning, it looks like
a dry day for most if not all of Wednesday. The exception would be
lingering chances of rain over the eastern zones in the morning.
Cold air advection behind the front is not strong, and temperatures
are expected to be well above normal.
Will maintain previous PCPN forecast for Thursday/Thursday night at
this time, although might need to include low chance PoPs in
association with a weakening cold front. Did however bump up high
temp forecast based on temps aloft. An onshore flow will keep
coastal sections cooler, but all areas once again will have high
temps above normal.
A low pressure system then approaches late in the week with
increasing chances of rainfall.
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --High pressure builds in tonight with winds becoming more
northerly. Winds will briefly decrease tonight before becoming
gusty again by morning.
Anticipate VFR conditions through the TAF period with little
cloud cover tomorrow.
.OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...
.Monday...VFR. NNW gusts near 20kt.
.Monday night-Tuesday evening...VFR.
.Tuesday night-Wednesday...MVFR possible in rain.
-- End Changed Discussion --
Westerly winds were a little weaker than forecast as low
pressure well to the north remains and slowly weakens. Also seas
were running up to a foot lower as a result of the weaker winds.
Winds and seas remain below Small Craft levels through this
evening. A cold front will push across the area waters this
evening and overnight, building seas to 4 ft and providing some
occasional gusts to 25 kt late tonight into Monday morning.
Will hold off on any headlines at this time, thinking that any
SCA conditions may only last for a few hours, if they occur at
all. No precipitation is expected with the frontal passage.
Following the cold frontal passage and as Canadian high
pressure builds southeast across the area. The next potential
chance of marine impacts will be late in the week on
Friday/Saturday as winds strengthen ahead of an approaching low
No hydrologic impacts are anticipated through the next 7 days.
The following are record high temperatures for today, and
Central Park....66 (1997).....67
LaGuardia Apt...65 (1997).....67
JFK Apt.........66 (1997).....65
Islip Apt.......60 (1997).....64
Newark Apt......66 (1997).....67