Area Forecast Discussion
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FXUS61 KOKX 201738
Area Forecast Discussion
National Weather Service New York NY
1238 PM EST Mon Feb 20 2017
High pressure builds in today, then shifts offshore tomorrow.
A weak warm front approaches the region Tuesday night and moves
through the area on Wednesday. The front remains near the
region into Thursday and Friday before lifting north as a warm
front Friday night into Saturday. Another cold front moves
across the region over the weekend.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Warming trend continues today with afternoon highs generally
expected to get up into the lower and middle 50s. This is
supported in the latest LAV and HRRR guidance, which are even
a bit underdone. Low-level cold advection behind cold front
today was overdone by models.
High pressure builds in from the NW today, and it`ll be
somewhat breezy due to the pressure gradient over the tri-state
area. Models are in good agreement with low RH through the
atmospheric column, so expect sunny conditions.
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
The surface ridge axis shifts in tonight and should be right over us
near daybreak. A clear sky with light to calm winds will allow for
good radiational cooling conditions tonight. Most spots fall below
freezing, with the exception being the city and adjacent suburbs.
Lows drop to around 20 across the northern fringe zones, and into
the teens for the Pine Barrens Region in eastern LI.
The high shifts offshore Tuesday. The resulting onshore flow and
subsidence will limit the mixing depth. After a sunny start, clouds
thicken with high-based overcast conditions expected in the
afternoon. With all of this considered, went closer to SuperBlend
for high temps, which are cooler than MAV and NAM MOS.
.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
The long term period period starts off somewhat unsettled as a
shortwave and weak surface cold front move across the region Tuesday
night. With best dynamics continuing north of the area, will
continue to go with chance pops for this time frame. Temperatures
remain above freezing and thermal profiles support an all liquid
event, so will expecting just plain rain with this event. Tuesday
night lows fall into the middle and upper 30s.
Behind the shortwave passage, weak high pressure builds into the
region. Heights aloft rise, allowing for a period of well above
temperatures. Highs on Wednesday are forecast in the upper 50s to
near 60. Slightly cooler conditions are expected across Long Island
and eastern and coastal Connecticut.
The warm unseasonable temperatures continue into Thursday as
westerly flow continues to pump warm air into the region. Will
follow previous forecast and continue to trend warmer than MOS and
model consensus blends which will likely be too cool on Thursday.
Highs for Thursday will likely approach 70 degrees in the NYC metro
and NE NJ and lower to middle 60s across the Lower Hudson Valley and
interior CT. Coastal CT and Long Island may struggle to get above 60
with a cooler flow off the waters. See Climate section for record
highs on Thursday (Feb 23rd).
Unsettled weather, and cooler but still above normal temperatures
return Friday and the weekend as the next low pressure system tracks
through the Great Lakes region and its associated frontal boundary
move across our region. Forecast models seem to differ on the timing
of each frontal system, so don`t think this entire period will
be wet. Regardless, chance of showers increases Friday night
into Saturday. Will continue to cap POPs at high chance. If the
cold front does move through by Sunday morning, a return to more
seasonable temps are expected.
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
High pressure builds over the region tonight, then offshore late
VFR through the TAF period with mainly clouds above 15,000 ft.
Northwest flow through 00Z, then winds veer to the northeast
overnight becoming light and variable. Southerly flow then
develops late Tuesday.
...NY Metro Enhanced Aviation Weather Support...
Detailed information, including hourly TAF wind component forecasts,
can be found at: http:/www.weather.gov/zny/n90
KJFK TAF Comments: Occasional gusts up to 20kt are possible
KLGA TAF Comments: Occasional gusts up to 20kt are possible
KEWR TAF Comments: Occasional gusts up to 20kt are possible
KTEB TAF Comments: Occasional gusts up to 20kt are possible
KHPN TAF Comments: Occasional gusts up to 20kt are possible
KISP TAF Comments: Occasional gusts up to 20kt are possible
.OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...
.Rest of Tuesday...VFR with southerly flow.
.Wednesday...MVFR or lower at times. Light rain possible.
.Thursday-Friday...MVFR or lower possible with mainly southerly
Cold air advection behind a cold front passage early this morning
will bring gusty conditions on the waters today with stronger gusts
generally over the eastern waters. The pressure gradient will have
sustained winds around 15 kt, and perhaps nearly 20 kt at times over
the eastern ocean waters. Models are in agreement however that winds
through the mixed layer and at the top of the layer are not very
supportive of 25+ KT gusts. Thinking is that there could be
occasional gusts to 25 KT, primarily over the eastern waters, but
the potential occurrence and coverage do not warrant a SCA.
Winds then subside through Monday night and remain light through
Tuesday as a high pressure ridge shifts into the waters.
A weak pressure gradient over the area waters Tuesday night through
Friday will result in winds and seas remaining below SCA levels.
The next chance for SCA conditions will be Friday night into
Saturday as the next low pressure and associated frontal system
No hydrologic impacts are anticipated through the next 7 days.
The following are record high temperatures for Thursday February 23,
Central Park........70 (1985)