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000
FXUS61 KOKX 290549
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1249 AM EST Sat Feb 29 2020

.SYNOPSIS...
Low pressure will gradually weaken over Canada through Saturday.
High pressure over the area on Sunday gives way to a slow
moving frontal system that will impact the area with multiple
waves of low pressure through mid week. High pressure will then
briefly follow for Thursday with a possible area of low pressure
impacting the area next Friday.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Winds should abate late tonight, with gusts more occasional.
There will be intervals of clouds, but generally a partly
cloudy to mostly clear night is expected. Lows will generally
be in the lower to mid 20s, except upper 20s NYC metro. This is
a bit below normal.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
Dry weather continues Sat and Sat ngt. Time heights suggest clouds
developing in the 5000-6000 ft range. A weak cold front should pass
in the late aftn, resulting in an increase in nwly winds. Moisture
is limited with the front so no pcpn is expected attm. All models
keep pcpn relegated to the higher elevations N and W of the fcst
area. The NBM was used for temps both Sat and Sat ngt. Clouds are
expected to decrease late Sat ngt, but winds again area expected to
stay up at least a little. There is a narrow late ngt window for
clearing and calm winds, and if this does occur, temps will be
several degrees colder than fcst.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Warmer and wetter will be the theme as we head into next week with
tons of uncertainty for the second half of the week.

The upper low retreats east of the Canadian maritimes with both
ridging aloft and at the surface building across the Northeast on
Sunday. This will be short-lived though as a nearly zonal flow to
start the week will send warmer Pac air into the region with
temperatures rising to 10 to 15 degrees above normal by mid week.

Global models start off in some resemblance of agreement as a
frontal system works into the area Monday into Tuesday, but
progresses slowly in response to a deepening northern branch upper
trough over the upper Mississippi Valley. Several waves of low
pressure will bring periods of showers, mainly from Tuesday night
into Wednesday. How much rain is uncertain, due to the complexity of
interaction between the two branches of the polar jet. The 12Z GFS
takes the closed low over the northern Baja at the start of next
week and phases it with the northern branch by mid week. This
results in a stronger frontal system and deeper low developing
across New England Wednesday into Wednesday. The GGEM and ECMWF
never allow this phasing, sending a weaker system through the area
Tuesday night into Wednesday morning. The southern branch closed low
then lifts off to the NE with a variety of solutions as it precedes
the next digging northern branch shortwave trough. Complex
interactions such as wavelength separation will determine whether
that low shoots off well to the south like the ECMWF, or is farther
north on Thursday like the GGEM with a potential winter weather
event. The GFS just takes that northern branch energy across the
area Friday as a clipper low with some light snow.

Bottom line, there are lots of solutions with low confidence for the
second half of the week. Thus, will keep chances of precipitation
low for the second half of the week. In fact, temperatures also will
be problematic depending upon which solution verifies. A colder
second half of the week is possible.
One would think that the nature of the pattern this winter would
lend credence to a more progressive pattern. However, there are no
signs of a pattern change in the long term. Stay tuned.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
Low pressure centered over southeastern Canada gradually weakens
overnight into Saturday afternoon as weak surface troughs move
through the terminals. Meanwhile, high pressure will slowly
build in from the west through Saturday night.

VFR through the TAF period.

Winds will be mainly west to northwest through the forecast,
with slight varying direction as surface troughs move across
the terminals. Overnight winds will be west 10 kt or less, with
occasional gusts at the NYC metro terminals to around 20 kt.
Winds and gusts increase Saturday morning to around 15 kt with
gusts 20 to 25 kt, and then increase a few more knots during the
afternoon as winds veer to NW. Northwest winds then diminish
Saturday evening, with the gusts coming to an end.

.OUTLOOK FOR 06Z SUNDAY THROUGH WEDNESDAY...
.Late Saturday night...VFR.
.Sunday...VFR. NW/W winds G15-20kt.
.Monday...VFR expected.
.Tuesday and Wednesday...MVFR or below with a chance of rain.

&&

.MARINE...
SCA conditions will remain on the ocean through at least
Saturday and will likely need to be extended into part of
Sunday. Elsewhere, marginal SCA conditions are possible.

High pressure moves east of the waters Sunday night into
Monday with an approaching frontal system through mid week with
multiple waves of low pressure. An extended period of SCA
conditions are forecast on the ocean waters in a SW flow from
Monday night into Wednesday. Conditions are more marginal
elsewhere.

&&

.HYDROLOGY...
No hydrologic impacts are expected thru the middle of next
week.

&&

.EQUIPMENT...
NYC NOAA Weather Radio Station KWO35 (162.55 MHz) is still
operating at reduced power.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EST this evening for ANZ350-
     353-355.

&&

$$
SYNOPSIS...DW
NEAR TERM...DW/PW
SHORT TERM...
LONG TERM...DW
AVIATION...JE
MARINE...DW/PW
HYDROLOGY...DW
EQUIPMENT...