Groton, Connecticut 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

824
FXUS61 KOKX 221128
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
628 AM EST Sun Dec 22 2024

.SYNOPSIS...
High pressure builds into the region through tonight and begins
to move offshore Monday. A weak frontal system approaches
Monday night and moves through Tuesday. High pressure builds
into the area Wednesday and remains in control through the end
of the week. A frontal system may approach the area by the
weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
** COLDEST AIRMASS OF THE SEASON **

High pressure builds into the region through today, bringing
the coldest airmass of the season so far. Temperatures will top
out from around 20 inland to the mid 20s along the coast, and
generally followed the previous forecast along with the latest
MOS guidance which are reasonable. While temperatures will be 15
to nearly 20 degrees below normal no record low maximum
temperature records are expected. As the center of the high
approaches later this morning into this afternoon gusty
northwest winds subside.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
The center of the high pressure will be moving over the region
by late tonight and with clear skies ideal radiational cooling
will take place, especially across the interior with snow
covered ground. Inland overnight lows will be near 5 degrees
lower than Saturday night`s lows, and along the coast
temperatures will be only a degree or two lower. Once again, no
record lows are expected, with lows 10 to 15 degrees below
normal.

The high begins to move offshore late Monday into Monday night.
The airmass begins to modify, and highs Monday will be 5 to 10
degrees higher than Sunday`s, but still below normal. With a
light return flow Monday night and clouds increasing in advance
of a clipper system, temperatures will fall after sunset, then
become nearly steady, and even begin to rise, especially along
the coastal areas. The low will be passing to the north Monday
night and light snow will be possible mainly after midnight.
With the system weakening as it approaches, and little moisture,
any snowfall will be light, with just a tenth or two.

The low passes across the region Tuesday, and precipitation
ends during the afternoon. Total snow accumulations are most
likely to be under 1 inch.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Large-scale upper level ridging moves in Tuesday night and into
Christmas Day with surface high pressure building in from the
north. This surface high pressure remains fairly stationary over
Southeast Canada filtering air down into the Northeast through
much of the next week under a persistent NE flow. Some weak
transient pockets of energy attempt to approach the area over
the crest of the ridge through the middle of the week, but with
the stationary high pressure holding steady, this should result
in some occasional cloud cover at most through the end of the
week.

By the end of the week and into the weekend, a digging trough
over the Central US approaches the area, but global guidance
differs in timing and orientation of the approach of a surface
low. As of now, kept a slight chance to chance of precipitation
in the forecast for the weekend, but it`s possible that the
frontal system holds off impacts to the area until the beginning
of the following week.

Given the persistent NE flow under a high pressure system
through much of the long term, temperatures will begin slightly
below average and gradually moderate through the week. High
temperatures Wednesday will be in the middle to upper 30s with
moderating temperatures through the week so that by the weekend,
highs will be in the low to middle 40s.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
High pressure builds across the terminals through Monday.

VFR through the TAF period.

NW winds 10-15 kt with gusts to 20-25 kt early this morning. Any
occasional gusts this morning should become more frequent after
sunrise before ending by 18Z. Light NW or VRB flow tonight as high
pressure builds in. Winds gradually shift out of the SSW Monday
afternoon.

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

Gusts may be occasional at times early this morning.

OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...

Monday: VFR.

Monday night-Tuesday: Chance of MVFR in light snow/light rain mix,
mainly into Tuesday morning.

Wednesday-Thursday: VFR.

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

&&

.MARINE...
Light freezing spray is possible this morning across portions of
the Long Island Sound, and along the south shore of Long Island
as gusty northwest winds continue and air temperatures remain in
the teens.

With gusty northwest winds around 25 kt, and ocean seas near 5
feet, a SCA remains on the ocean waters until 100 PM EST. With
high pressure building toward the waters, wind gusts and ocean
seas are expected to fall below advisory levels by then. Winds
and seas then remain below advisory levels across all the waters
tonight through Tuesday. And sub-SCA conditions are expected
Wednesday through Friday with high pressure in place and a weak
pressure gradient over the area.

&&

.HYDROLOGY...
There are no hydrologic concerns through next weekend.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 1 PM EST this afternoon for ANZ350-
     353-355.

&&

$$

SYNOPSIS...MET/MW
NEAR TERM...MET
SHORT TERM...MET
LONG TERM...MW
AVIATION...MW
MARINE...MET/MW
HYDROLOGY...MET/MW