FXUS61 KOKX 100227

Area Forecast Discussion
National Weather Service New York NY
927 PM EST Sun Dec 9 2018

Southern low pressures pass well south and east of the region
overnight into Monday. A weakening front passes overnight with
another cold front mid week. Otherwise Canadian high pressure
remains in control through Thursday. Low pressure approaches
from the west on Friday and passes through next weekend.


The forecast is on track with only minor adjustments made to
hourly temperatures and dewpoints with this update.

A split upper flow remains across the region tonight, with a
southern stream shortwave and associated low pressures tracking
off the southeast coast. Meanwhile a northern stream trough
moves into northern New England, with associated surface low
moving through.

Surface ridging gets squeezed between the two systems, with a cold
front approaching from NW but likely dissipating before reaching the
area. High cloud shield eventually slides east overnight, but
potential for lake sourced strato-cu field to work into far NW
hills towards morning. Otherwise, expect a bit of a tightening
N gradient in the wake of departing low pressure. The
combination will likely limit radiational cooling to a brief
window across outlying areas late. Lows generally in the teens
across outlying areas, with upper 20s for NYC metro.


Split upper flow continues during this period. Southern stream
trough gets invigorated and persists across the SE US, while
northern troughing persisting across Quebec and a northern
stream shortwave approaching the Great Lakes. The region will
transition from a zone of gentle upper confluence to greater
northern stream influence during this period. The result will
be Canadian surface high pressure building towards the region
behind a dissipating cold front, and overall continuation of dry
and chilly weather.

Despite sunshine, temps will likely only reach the mid to upper
30s once again. Likely good radiational cooling across outlying
areas Monday night, with temps dropping to lower teens, while
NYC metro remains near freezing.


High pressure on Tuesday brings us another dry day with high
temperatures below normal. An upper trough shifts through the region
Tuesday night into Wednesday morning with a surface reflection in
the form of trough. Models continue to show a lack of moisture with
these features, so will continue to go with a dry forecast. Ridging
then resumes aloft during the remainder of Wednesday with a mostly
sunny sky and below-normal high temperatures. High pressure then
continues to dominate the weather pattern for Thursday, and will be
centered offshore for Friday. This may allow for light rain to shift
in from the south and west during the afternoon, but better chances
for rain will be Friday night and Saturday. The rain will be
associated with a storm taking shape to our west late in the week
before eventually passing through or at least nearby during next
weekend. Have capped PoPs at 50% due to the uncertainty in timing,
but it`s looking likely that we`ll have rain at some point Friday
night into Saturday. Rain chances diminish by Sunday with global
models in agreement that the center of the storm will be to our east.


High pressure remains over the region as a weakening trough
passes overnight.

VFR conditions will prevail as high clouds depart by Monday.
Light NW winds overnight remain NW to N through Monday. Speeds,
particularly along the coast, increase to around 10 kt Monday
morning, and a few gusts to 15-19 kt cannot be ruled out. Winds
diminish as the afternoon progresses.

.Monday night-Thursday...VFR.
.Friday...VFR, then a chance of Sub-VFR late in rain.


Tranquil winds and seas are expected for most of the overnight
as high pressure remains overhead. Occasional NW gusts to 25 kt
are possible Monday morning over ocean waters with a tightening
gradient and shot of cold air in wake of departing southern
low. At this point, since it is marginal and of short duration,
will hold off on SCA, but if guidance trends a bit stronger
will likely have to issue a short fuse SCA. Otherwise, winds are
generally expected to remain below SCA thresholds through
Tuesday as high pressure builds into the area. May have another
shot of brief SCA winds Tuesday night into Wed in wake of
another cold front.

Ocean seas will build late Monday into Monday night due to a
south to southeasterly swell from a series of low pressure well
offshore. Ocean seas may occasionally flirt with 5 ft Monday
night into Wednesday.

Better chance for SCA conds appear to be late week into the
weekend with an approaching low pressure system.


Dry conditions are expected through at least most of Friday.

A moderate to heavy rainfall could occur Friday night into next
weekend, but rain amounts and potential impacts are uncertain
at this time.


NYC Central Park winds are out of service until further notice.
Loss of data is due to a severed cable. Parts are on order.

NYC NOAA Weather Radio Station KWO35 (162.55 MHz) will remain off
the air for an extended period of time.





NWS OKX Office Area Forecast Discussion