discussion on 2024-03-17

000
FXUS61 KOKX 172115
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
515 PM EDT Sun Mar 17 2024

.SYNOPSIS...
Deepening low pressure will track slowly east across eastern
Canada to start the week. A series of weak cold fronts and/or
troughs will swing through the area Monday into Monday night.
Low pressure brings a cold front through the area on Wednesday.
High pressure then briefly moves in for Thursday with another
frontal system possible for Friday and into the weekend.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
-- Changed Discussion --Temperatures have been running warmer than forecasted while
dewpoints have been drier. Have adjusted the forecast based on
the latest observations. ALl else remains on track.

A digging upper trough over the Great Lakes will drop into the
eastern third of the country to start the week. At the same time,
deepening surface low pressure over eastern Canada will track
slowly east. This will allow for a cooler airmass to start work
into the region tonight. Still though, with west winds staying
up a bit, lows tonight will range from the lower 30s inland to
the upper 30s/lower 40s at the coast. This is about 5 degrees
above normal.-- End Changed Discussion --

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/...
A gradual cool down is expected during this time as an upper
trough moves across the area through Monday night, then offshore
on Tuesday. This will allow for temperatures close to seasonable
levels on Monday, but trending to a few degrees below normal by
the time Tuesday arrives.

In addition, low pressure will track slowly east across eastern
Canada during this time, while high pressure drops south from
the Central Plains to the Gulf coast. This will maintain a gusty
west flow during with daytime gusts of 20 to 30 mph, highest on
Tuesday. In addition, this will be combined with an anomalously
dry airmass with RH values of 30 to 40 percent each afternoon.
This will aid the spread of any wildfires that develop. See
Fire Weather Section below.

Expect mainly dry conditions, but some of the CAMs are hinting
at a brief sprinkle and/or shower Monday aft/eve north and west
of the NYC metro. For the time, have kept it out of the forecast
with the dry, subsident west flow.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
A large upper level trough over the Northeast remains in place
midweek with cooler temperatures for the area. Embedded energy in
the trough approaches from the northwest on Wednesday brining with
it an associated surface low pressure system. This low passes to our
north, dragging a cold front through the area during the day on
Wednesday. This may bring a few showers to the northern half of the
CWA, though a lack of moisture will prevent there being widespread
precipitation.

The cold front moves through by Wednesday night with high pressure
attempting to build in from the west. As the low to the east pulls
away and the high pressure approaching from the west, a tightening
pressure gradient will allow for increasingly breezy northwest winds
to advect cooler air into the area for Thursday.

Heights rise a bit as the mid-level flow become more zonal and high
pressure moves over the area. Models then differ as to the handling
of the potential next system. The GFS brings a low to our south and
a low to our north near the area, bringing a round of rain/snow
Friday night with high pressure settling in over the weekend. The
GDPS has a slower coastal low over the Carolinas track nearby to our
south, bringing better chances for precip to southern portions of
our CWA on Saturday, with high pressure to the north keeping it from
moving directly into the region. The ICON and ECMWF bring a weak
disturbance from the west and north on Friday night, with high
pressure building over the weekend as a delayed coastal low to our
south is unable to impact us. Given the discrepancies in these
solutions, have only kept chance POPs in the forecast during this
time frame due to lingering uncertainties. All models do agree on
some upper-level ridging into the weekend.

Temperatures for the extended period will be largely at or below
average. Temperatures in the upper 40s to lower 50s on Wednesday,
dropping into the low to middle 40s for Thursday through Saturday.

&&

.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
High pressure builds in from the southwest through the forecast
period.

VFR conditions are expected through the TAF period. KSWF may see a
shower move through early this evening, but confidence was not high
enough to include in the TAF.

W to WNW winds through the TAF period. Sustained winds of 15-20 kt
this afternoon with gusts of 25 to 30 kt. Winds diminish this
evening, around 23Z or thereafter. Gusts return around 15Z Monday,
slightly weaker, at 20 to 25 kt. An isolated gust to 30 kt is
possible.

 ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

Start and end time of gusts could be 1-3 hours off from forecast.

OUTLOOK FOR 18Z MONDAY THROUGH THURSDAY...

Monday: VFR. W to WNW winds 10-15G20-25kt, becoming WNW in the
evening

Tuesday: VFR. WNW winds 15G20-25kt.

Wednesday: Mainly VFR. Slight chance of rain inland, possibly mixed
with snow. W winds 10-15G20kt.

Thursday: VFR. WNW winds 10-15G20-25kt.

Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90

&&

.MARINE...
Marginal SCA conditions through Monday. Current SCA on the ocean
waters east of Fire Island Inlet is set to expire before
midnight. Confidence is too low to issue for gusty westerly
flow on Monday. However, confidence increases Monday night into
Tuesday with a chance of a SCA on all waters.

Near Small Craft conditions possible on the ocean Tuesday night
but gradual subsiding in the wind and waves should allow for
sub-SCA conditions on all waters by Wednesday morning. A
tightening pressure gradient by Wednesday afternoon and evening
will allow for widespread small craft conditions on all waters
by Wednesday evening. SCA conditions likely persist through the
day on Thursday before gradually subsiding Thursday night. Sub-
SCA conditions are expected through Friday.

&&

.FIRE WEATHER...
Drier conditions are expected Monday with the minimum relative
humidity 30 to 40 percent, with a west wind 10 to 15 mph, and
gusts 20 to 25 mph. An SPS has been issued for the state of CT
for elevated fire weather concerns on Monday. This was coordinated
with state partners.

Tuesday and Thursday minimum relative humidity will again range
from 25 to 30 percent, with Wednesday`s 35 to 45 percent. Gusty
westerly winds are expected during the day Tuesday through
Thursday. The highest winds and gusts are expected Thursday with
winds 15 to 20 mph and gusts 25 to 30 mph.

&&

.HYDROLOGY...
No hydrologic impacts are expected through the forecast period.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 11 PM EDT this evening for ANZ350-
     353.

&&

$$

SYNOPSIS...BR/DW
NEAR TERM...BR/DW
SHORT TERM...DW
LONG TERM...BR
AVIATION...JP
MARINE...BR/DW
FIRE WEATHER...
HYDROLOGY...BR/DW