Forecast Discussions mentioning any of
"HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 12/13/21
Area Forecast Discussion
National Weather Service New York NY
922 PM EST Sun Dec 12 2021
.SYNOPSIS...
High pressure settles southwest of the region Monday into
Monday night before moving offshore. A second area of high
pressure builds to the north Tuesday into Tuesday night. High
pressure moves off the New England coast Wednesday and Wednesday
night allowing a warm front to approach and move north
Thursday. A cold front moves across the region Thursday night
into early Friday as the associated low tracks well to the
north. High pressure briefly builds Friday as a wave of low
pressure quickly approaches Friday night and affects the area
into the beginning of next weekend.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Updated for current conditions, mainly dew points and
temperatures. Forecast remains on track.
Upper ridging and drier air continue building in from the west.
At the surface, high pressure was located southwest of the
area, and dry conditions are expected through the period. There
may be some scattered cirrus clouds late tonight as they spill
over the ridge.
Dewpoints tonight will bottom out in the upper teens to lower
20s, however westerly winds should remain up, 5-10 mph,
mitigating any possible radiational cooling. Low temperatures
therefore should remain in the mid to upper 30s across NYC and
coastal locations and the upper 20s in the interior and across
the Long Island Pine Barrens, under the westerly flow.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
Surface high pressure and dry conditions will dominate the
short term. The high south of the area will weaken and slide
offshore Monday afternoon and evening, while a secondary surface
high builds north of the area by Tuesday night.
Breezy southwesterly to westerly winds and dry conditions will
continue on Monday, as high pressure remains to our south. Gusty
winds are supported by HRRR 10m gust potential, which is
depicting 15-20 mph gusts for much of the day Monday, especially
across the eastern CWA.
For temperatures, went slightly below MOS, to near the NBM 90th
percentile for highs for Monday, in the low to mid 50s, given
the predominant westerly flow, which is 5-8 degrees above
normal.
Low temperature reasoning remains similar to Sunday night for
Monday night. Winds will begin to diminish toward daybreak on
Tuesday, however, potentially allowing for a few hours of
radiational cooling under nearly cloudless skies. Forecast lows
range from the mid and upper 30s for coastal spots, with upper
20s and low 30s inland.
High pressure builds in from the north on Tuesday, again
keeping the area dry under large scale subsidence. High
temperatures will be similar to Monday, in the low and mid 50s
areawide. Winds veer to the northeast and east late Tuesday as
the high to the north begins to move offshore.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
The models and ensembles continue to be in good agreement
through much of the extended forecast period, especially for the
frontal system that will be impacting the region Thursday and
Thursday night. Some uncertainty develops with the strength and
placement of a frontal wave developing across the central US and
tracking quickly through the northeast and mid Atlantic states
for the beginning of next weekend. There also remains good
continuity from previous forecasts, so mainly used the NBM
guidance through the extended. Temperatures from Wednesday into
Saturday night remain above normal with the peak of the warmth
still expected for Thursday as a deep southwesterly flow brings
well above normal temperatures to the east coast. Guidance has
increased the highs slightly for Thursday, and with the highly
anomalous warmth expected leaned toward the 75 percentile for
Thursday`s highs. As a result, at this time, temperatures will
be approaching record levels at a few of the climate sites.
Temperatures will be near 15 degrees, to possibly as much as 20
degrees, above normal for Thursday. For Saturday there is
uncertainty as to the amplification of the northern stream
longwave trough that tracks quickly from the Pacific northwest
Thursday and to the Great Lakes region Saturday. Behind this
system temperatures are expected to return to seasonal levels
for Sunday.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
VFR through the TAF period with high pressure building south of
the region.
W-SW winds 5-10 kt are expected tonight, strongest at NYC terminals.
SW winds continue on Monday and increase to 10-15 kt. Gusts
17-20 kt should occur middle to late morning and continue into
the afternoon, ending late in the afternoon. SW winds fall back
to 10 kt or less in the evening.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Gusts on Monday may end up occasional.
.OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
.Monday night-Wednesday...VFR.
.Thursday...Mainly VFR, slight chance of showers at night.
.Friday...VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Expecting SCA conditions to continue through Monday and
potentially Monday night for the ocean waters, mainly for seas.
However, gusts may approach SCA levels on the ocean waters
overnight as high pressure builds to the south and the gradient
increases once again. Even across the Sound east of the mouth of
the Connecticut river and possible the eastern bays may have
gusts approaching SCA levels later tonight. Once conditions
improve on the ocean waters late Monday or Monday evening, sub
SCA conditions will remain into Tuesday night.
Winds and seas will be below SCA levels Wednesday and Wednesday
night across all the forecast waters. An increasing
southwesterly flow behind a warm front Thursday may allow for
gusts to approach or exceed SCA levels across the ocean waters
as seas build to SCA levels. Small craft conditions are then
expected on the ocean waters into early Friday, with conditions
subsiding below SCA levels from west to east during the day and
possibly into Friday evening as low pressure tracks well to the
north and high pressure builds in from the west.
&&
.HYDROLOGY...
No hydrologic impacts are anticipated through Sunday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 7 PM EST Monday for ANZ350-353-355.
&&
$$
SYNOPSIS...DBR/MET
NEAR TERM...DBR/DS
SHORT TERM...DBR
LONG TERM...MET
AVIATION...DS
MARINE...DBR/MET
HYDROLOGY...DBR/MET