Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
655 PM EST Wednesday Nov 25 2015
high pressure over the region will slowly drift eastward through
Friday...giving way to a cold front this weekend. High pressure
builds late this weekend into early next week. A complex storm
system will approach from the west middle week.
Near term /until 6 am Thursday morning/...
drops temperatures significantly eastern Li this evening. Otherwise the forecast was
High pressure near the region starts to move east of the
region...resulting in an onshore flow. This will result in warm air
advection and an increase in low level moisture. As a low level
inversion develops...clouds develop late tonight into Thursday
morning as the inversion steepens. Otherwise...expect light winds
and dry conditions. Temperatures overnight fall into the 30s and
40s...except far north and west of NYC...where temperatures fall
into the middle and upper 20s...where clouds will take longer to
develop and radiational cooling takes place. Used a mav/met blend
for overnight lows.
Short term /6 am Thursday morning through Thursday night/...
warm advection continues Thursday...with a mostly cloudy day. In
addition...some low level lift will allow for the chance of some
drizzle to develop during the morning and continue through the day
and possibly into Thursday night. Will go with just slight chance
probability of precipitation for now...thinking that it will remain mostly dry.
The clouds should start to dissipate late Thursday night...but will
continue to carry a mostly cloudy night.
Temperatures will be above normal on Thursday with highs in the 50s.
Lows Thursday night fall into 40 and lower 50s. Mav/met guidance was
in good agreement and used.
Long term /Friday through Wednesday/...
much of the forecast based on blended model/MOS data.
Low level flow begins to turn toward the S/SW ahead of a cold front
Friday. As such...low level moisture should not be as pronounced
and do not foresee any drizzle.
The cold front is associated with a middle and upper level trough that
will traverse across the Great Lakes region. The front likely
approaches the area Friday night...moving through late Friday night
or Saturday morning...as timing differences are noted. NAM much
slower than latest GFS...with operational European model (ecmwf) timing Sat morning.
A few showers may accompany the front as it moves through...but
the combination of limited available moisture and weak lift should
preclude higher coverage of showers producing measurable rainfall.
Due to upper trough/steering flow...most model solutions support cold
front remaining nearly stationary just south of the area as high
pressure builds to the north Sunday and Monday. A few showers along
the front may clip portions of the area...but feel most of the
region remains dry.
As the upper trough moves east...weak ridge builds temporarily
Monday into Tuesday before northwest/Upper Middle west trough tracks east
toward the Great Lakes region.
It appears that low pressure will develop along a frontal boundary
that extends from Texas/la northward toward in/OH. This low pressure
deepens in time early next week as it moves northeast ahead of the
Timing and positional differences are noted...but with retreating
high pressure...will ramp up probability of precipitation late Tuesday through Tuesday night for
now...much like previous forecast.
Above normal temperatures Friday should give way to closer to normal
readings Saturday through early next week. Followed blended models
data which was reasonably close to wpc guidance.
Aviation /00z Thursday through Monday/...
high pressure ridge remains over the region.
VFR. Light east to southeast winds for terminals where light and variable
winds are not forecast.
For Thursday...VFR likely...but a period of ceilings 3000-4000ft
possible in the afternoon. Southeast winds under 10kt.
... 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: no unscheduled amds expected.
Klga fcster comments: no unscheduled amds expected.
Kewr fcster comments: no unscheduled amds expected.
Kteb fcster comments: no unscheduled amds expected.
Khpn fcster comments: no unscheduled amds expected.
Kisp fcster comments: no unscheduled amds expected.
Outlook for 00z Friday through Monday...
Thursday night...VFR/MVFR ceilings.
Friday...chance MVFR am...otherwise VFR.
Saturday-Saturday night. MVFR possible in -shra. Chance for north-NE
gusts 20kt Sat PM.
high pressure will slide east of the waters through Thursday
night. A weak pressure gradient will exist across the forecast
waters. As a result both wind and seas will remain below Small
Craft Advisory levels through Thursday night.
High pressure over the waters will give way to an approaching cold
front Friday night into Saturday. High pressure builds to the north
behind the front late this weekend and into early next week.
As such...winds will remain below Small Craft Advisory thresholds...or 25 kts through
this time frame.
A southeast swell may result in seas close to 5 feet over the ocean waters
Friday and into Saturday. Otherwise...seas remains rather tranquil
through the weekend and into early next week.
no significant precipitation is expected through Thursday night.
short term...British Columbia
long term...precipitable water