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000
FXUS61 KOKX 220545
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
145 AM EDT Tue Oct 22 2019

.SYNOPSIS...
A frontal system approaches today and passes across the region
tonight. High pressure will build over the region through the
middle of the week. A frontal system may impact the area late
Friday into Saturday, with another possible by the end of the
weekend.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Clouds will continue to increase through the early morning
hours. A northeast flow will begin to go more easterly closer
to daybreak resulting in an increase in overall lower level
moisture. It will remain dry with lows mainly at or slight
above normal. Temperatures may level off towards daybreak as
clouds thicken.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
A vertically stacked and occluded low pressure system over the Upper
Midwest will lift northeast into Canada later Tuesday into Tuesday
night. A complex frontal system to the east and southeast of
the storm will approach during the day on Tuesday bringing
extensive cloud cover in advance of a warm front. Despite good
upper level amplitude, with an overall lack of blocking to the
northeast I do expect the warm front to get through during
Tuesday evening in most places, followed by the cold front for
later Tuesday night, early Wednesday morning.

As far as precip timing and intensity, with the dynamics going
well north of the region we are not anticipating a significant
rainfall event. There should be enough thermal forcing to result
in a light rainfall event where precip amounts average around a
half inch across the CWA, with some higher amounts closer to
three quarters of an inch perhaps across northern and
northwestern sections. The rain should be quite light during the
day on Tuesday with the steadier rain approaching far western
sections during the afternoon hours, say around 20z or so. There
will be some drier air in the mid levels which will preclude any
steadier rainfall until mainly the evening hours. The steadiest
rainfall should fall between 1z and 6z across much of the
forecast area. Towards daybreak Wednesday morning the last of
any rain showers should be getting ready to exit far eastern
sections. Temperatures on Tuesday will average near normal, and
above normal Tuesday night.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Rain will taper off from west to east on Wednesday as the frontal
system pulls away. A westerly breeze can be expected, drying the
area out by afternoon. The NBM was used for temperatures. Winds will
lighten and skies clear Wednesday night. The CONSMOS was favored,
allowing for better radiational cooling. Sunny with highs in the
lower 60s on Thursday with high pressure centered southeast of the
forecast area. The NBM was used for temperatures. A clipper type
system is then progged for late Friday into Saturday. The ECMWF has
consistent timing and placement with the 00Z and 12Z runs. The GFS
is further north with the main low. A band of chilly moderate rain
can be expected with an ECMWF solution, with a few showers possible
under the GFS scenario. A blend of the model data was used for
precipitation probabilities. The NBM was used for temperatures
Friday through Saturday, with the CONSMOS used Saturday night. A
chance of rain returns Sunday and Monday due to a southern stream
upper low and Gulf of Mexico moisture. The ECMWF is the wet model
with this, with the GFS now dry through the period. The NBM was used
for temperatures.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
Low pressure system and a cold front approach today and move
across the region tonight.

A mainly VFR forecast through the first half of tonight becoming
MVFR towards daybreak for all terminals lasting through the
day and into Tuesday night. Isolated IFR conditions may be
possible with some of the rain with the actual frontal passage.

Expect light rain showers or drizzle to develop during the
afternoon hours, becoming a more steady rain this evening and
into the overnight. In addition, expect some lowered
visibility. There is some uncertainty with the arrival time of
lower conditions.

NE-N winds averaging around 5-10kt. Winds veer more ENE late
afternoon and evening. Southerly winds prior to the frontal
passage will be possible in the late evening. Winds become
northerly behind the cold front between 06-12z Wednesday.

.OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...
.Tuesday night...MVFR/IFR rain at night.
.Wednesday-Thursday...VFR. Chc W gusts 20-25kt on Weds.
.Friday-Saturday...Chc MVFR and rain Fri PM into SAT AM.

&&

.MARINE...
Small Craft conditions are expected to continue on the ocean
through at least the day on Wednesday. A dominant easterly swell
will result in rough seas with a period of around 9 seconds,
and with waves much of the time running at least 5 to 8 feet for
the ocean waters. By Wednesday the winds are expected to
increase to where gusts will approach 25 kts out on the ocean.
Sub SCA conditions are expected for the non-ocean waters during
this time frame, with marginal small craft advisory winds on the
protected waters by Wednesday. Conditions improve Wednesday
night through Friday. Small Craft Advisory conditions may be
needed over the weekend depending on the strength and position
of a frontal system.

&&

.HYDROLOGY...
No significant rainfall is anticipated through the forecast
period.

&&

.TIDES/COASTAL FLOODING...
Water levels during this afternoons high tide along the south
shore back bays will likely fall short of minor coastal flood
benchmarks. No statements have been issued at this time based on
the latest forecast water levels.

&&

.EQUIPMENT...
NYC NOAA Weather Radio Station KWO35 (162.55 MHz) remains off the
air.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 8 PM EDT Wednesday for ANZ350-353-
     355.

&&

$$
SYNOPSIS...JE
NEAR TERM...DS
SHORT TERM...JE
LONG TERM...BC
AVIATION...BC
MARINE...
HYDROLOGY...JE
TIDES/COASTAL FLOODING...
EQUIPMENT...