Scientific Forecaster Discussion
fxus61 kokx 251058
Area forecast discussion
National Weather Service New York New York
558 am EST Sat Nov 25 2017
high pressure just to the south will weaken today as offshore low
pressure passes well to the southeast. A cold front will approach
late today and move across this evening, followed by high pressure
from Sunday through Tuesday. Another cold front will move across
on Wednesday. High pressure will build in briefly Wednesday
night, and then pass to the north as the next storm system
approaches on Friday.
Near term /until 6 PM this evening/...
SW flow between the weakening high to the south and the
approaching front will lead to one mild day, with temps rising
into the mid and upper 50s. Guidance has dry and a little
slower with the front for the daytime hours today, so skies
should remain mostly sunny for the bulk of the day, becoming
mostly cloudy late only northwest of NYC.
Short term /6 PM this evening through Monday/...
the cold frontal passage tonight should be mainly dry, with only
a slight chance of rain showers across southeast CT. This slight chance
should continue into the early daylight hours on Sat with the
passage of a vigorous mid level shortwave, at which time it may
be cold enough there inland for a few wet snowflakes to mix in
early Sunday morning. Fair and brisk wx should return with near
seasonable temperatures for later Sunday into Monday.
Long term /Monday night through Friday/...
high pressure will build in through Tuesday, with near seasonal
normals. A frontal system is then expected to move across on
Wednesday, with temps ahead of that front rising well into the
50s, then returning to near seasonable levels Wed/Thu before
another storm system moves across on Friday.
Aviation /12z Saturday through Wednesday/...
a cold front approaches from the Great Lakes today, moving
across this evening.
VFR, outside of low prob of a sparse shower this evening with
frontal passage, and low prob of a sparse rain/snow shower
early Sun morning with passage of upper disturbance.
S/SW winds today, with occasional gusts into the mid teens
possible for south coastal areas. Windshift from ssw>w/west-northwest
(around 310 magnetic) this evening, with west/west-northwest gusts of 15 to
20 kt possible for NYC/New Jersey Metro terminals late this evening. Northwest
wind g20-30kt likely developing late tonight for NYC/New Jersey
Outlook for 12z Sunday through Wednesday...
Sunday...VFR, outside of an isolated am rain/snow showers for
eastern terminals. Northwest winds g25-30kt, with isolated gusts to 35
Sunday night...VFR. Nw>w winds g15-20kt.
Monday-Monday night...VFR. West/northwest winds g15-25kt, diminishing
Tuesday-Tuesday night...VFR. SW winds g15-25kt.
Wednesday...VFR. W>nw winds g15-20kt.
as high pressure south of the ocean forecast waters weakens
tonight and one low moves off the southeast coast as another
moves through southern Canada, the pressure gradient force will
increase through tonight. This will allow for SW winds to
increase. However, winds and gusts are expected to remain below
Small Craft Advisory levels until a cold frontal passage tonight. Strong Small Craft Advisory
conds then expected on all waters on Sunday, with frequent gusts
up to 30 kt and occasional gusts up to 35 kt. Did not go with a
gale headline as these stronger wind gusts may be sporadic in
Small Craft Advisory conds likely to continue on the ocean and eastern sound
into Monday, with Max ocean seas up to 6 ft.
Ocean seas might rise to Small Craft Advisory conditions again Tuesday night into
Wednesday ahead of the next frontal system.
no hydrologic impacts expected.
Marine...Small Craft Advisory from 1 am to 6 PM EST Sunday for anz350-