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Area forecast discussion...resent 
National Weather Service New York New York
455 am EST Wednesday Jan 28 2015

Synopsis...
high pressure builds in today from the west. The high moves off the
coast Thursday. A clipper system affects the area Thursday night
and Ushers in very cold air starting Friday afternoon. High
pressure builds in from the west Friday night through Saturday
night...then slides to the east on Sunday. A storm system
approaches from the southwest late Sunday...then passes near the
region on Monday. More cold high pressure then builds in Monday
night into Tuesday.

&&

Near term /until 6 PM this evening/...
light snow finally diminishing over southern CT and most of
Suffolk County. Activity was best detected by the latest rap. All
indications are that this dissipates before sunrise. The kokx
radar showed an enhanced area passing right over the office where
1/2" was measured at 06z. Would suspect that the twin Fork may
have picked up an inch ot possibly 2.

Special weather statements were issued to ensure dot folks are aware
of this.

Winds gusting to 25 miles per hour will result in some blowing snow.

Skies are now mostly clear west of bdr to frg. Expect this clearing
to spread east during the day.

Despite sun...winds keep boundary layer well mixed and high albedo
from the fresh snow keeps maximum temperatures confined to the middle 20s. Used
1-2 degrees below the lower of the combined MOS.

Apparent temperatures (wind chill) in the lower teens.

&&

Short term /6 PM this evening through 6 PM Thursday/...
upper trough departs with ridge building in tonight. Sky clear and light
wind. Lows in the single digits to around zero inland. Middle teens
for the city and around 10 on Long Island. Again...the lower of the
MOS was used and lowered 1-2 degrees from there. Feel these might
still be too warm...but usually loose when trying to out forecast
MOS too much.

Warm air advection advection set up on Thursday with cloud cover thickening and
lowering from west to east. Expect to be overcast by middle afternoon even out
east. Temperatures are not as cold - around 30...lower 30's New York metropolitan and
Long Island.

Keep probability of precipitation just west of Orange County through 6 PM per consensus of
latest nwp including sref.

&&

Long term /Thursday night through Tuesday/...
not a lot of changes with this package. Two systems - Thursday night
into Friday and then Sunday night into Monday.

Confidence is high for Thursday night into friday's clipper system
as nwp has been very consistent. The uncertainty lies with boundary
layer temperatures. Expecting temperatures along the coast will be marginal. Have
kept this mostly snow - though a wet snow for the coast.
Probabilistic snow graphics and data are available at:
weather.Gov/okx/winter

Clipper pulls an Arctic front across the region with a massive drop
in temperatures during the late afternoon into the evening Friday. Have some
concern for a flash freezing of residual moisture during the evening
commute. Forecast middle teens in the city by 7 PM.

Winds howl Friday night with ambient temperatures to near zero inland with
middle single digits at the coast. Looks likely for wind chill
advisories !!

Jumping to next Sunday night-Monday...a progressive system will
track out of Texas. Nwp has been rather consistent with this
scenario. The details of this system though remain highly uncertain.
Have raised probability of precipitation along with all surround National Weather Service offices to likely. Have
not adjusted temperatures and continue with the cold solution. This is
supported by the gefs mean (not the operational GFS which is warm)
and to a lesser extent the operational European model (ecmwf). CMC is warmest i've
seen - all rain and a lot of it (don't need that either).

Will add this to the hazardous weather outlook at this time.

&&

Aviation /10z Wednesday through Sunday/...
ow pressure south of Nova Scotia will weaken and move farther
away as high pressure builds from the west.

Leftover bands of light snow could bring tempo MVFR conds to
kbdr/kisp/kgon before daybreak...otherwise mainly VFR conds
expected today. Winds will generally be out of the northwest /right of
310 magnetic/ at 10-15 knots. Gusts 20-25 knots will be sporadic at
first...then become more frequent by 14z.

New York metropolitan enhanced aviation weather support...

Detailed information...including hourly taf wind component forecasts
can be found at: http:/www.Erh.NOAA.Gov/zny/n90 (lower case)

Kjfk fcster comments: high confidence in winds remaining right of
310 magnetic today.

Klga fcster comments: high confidence in winds remaining right of
310 magnetic today.

Kewr fcster comments: high confidence in winds remaining right of
310 magnetic today.

The afternoon kewr haze potential forecast is green...which
implies slant range visibility 7sm or greater outside of cloud.

Kteb fcster comments: high confidence in winds remaining right of
310 magnetic today.

Khpn fcster comments: high confidence in winds remaining right of
310 magnetic today.

Kisp fcster comments: high confidence in winds remaining right of
310 magnetic today.

Outlook for 00z Thursday through Saturday...
Wednesday night-Thu...VFR. Diminishing winds.
Thursday night-Friday morning...IFR conds likely in snow...especially
inland...as developing low pressure moves through. Snow could mix
with rain on Long Island.
Friday afternoon-night...mainly VFR. Northwest winds g20-30kt increasing at
night as the offshore low intensifies offshore.
Sat...VFR.
Sun...MVFR or lower conds and gusty winds likely...as another
low impacts the area. Low track and therefore details on precipitation
type and winds uncertain.

&&

Marine...
the Nor'easter weakens and exits over the Canadian Maritimes as high
pressure builds in.

Small Craft Advisory gusts continue today for all waters. Seas gradually subside.

Tranquil conditions tonight into Thursday evening. The pressure
gradient begins to increase Thursday night...with at least Small Craft Advisory level
seas possible on the coastal waters late Thursday night.

A tightening pressure gradient and strong low level cold advection
makes gale conditions likely on all waters from Friday afternoon
into early Saturday. Freezing spray added to forecast with temperatures
well below sst's.

Sub Small Craft Advisory conditions should develop on all waters by late Saturday
night...and continue on Sunday...with high pressure gradient over
the region.

&&

Hydrology...
no significant precipitation through Sunday. Some light snow is
likely Thursday night into Friday...but no hydrologic impact is
expected.

There is the potential for at least a half an inch or so of liquid
equivalent from Sunday night into Monday. Some or most of this is
currently forecast to be in the form of frozen precipitation...so
little or no hydrologic impact is expected. However...a warm
solution for this system is a possible and most precipitation
could be of liquid with up to 2 inches possible. This would produce
hydrologic concerns...especially over areas just receiving a foot
or more of snow.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 6 PM EST this evening for anz330-
335-338-340-345-350-353-355.

&&

$$
Synopsis...tongue
near term...tongue
short term...tongue
long term...tongue
aviation...Goodman
marine...tongue/pw
hydrology...tongue/pw

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