Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
1007 am EST Thursday Nov 27 2014
low pressure departs to the northeast today. An upper level
disturbance will pass through before high pressure builds Friday.
The high moves east this weekend. A warm front will lift through on
Sunday...followed by a cold front late Monday. Another high will
build from the north into the middle of next week.
Near term /until 6 PM this evening/...
the upper level short wave moving NE toward the area is causing greater areal
coverage of snow / rain showers.
Until 17z or noon...increased probability of precipitation to nearly 50% across
portions of the lower Hudson Valley and northern New Jersey. Also increased
chance of precipitation across entire local area...with precipitation type falling mainly
as snow at temperatures lower than 38 degrees and mainly as rain above 38 degrees.
Temperatures rise through the 30s today. High temperatures should range from the
middle 30s to around 40. Followed a MOS blend which seems to agree
with forecast profiles and expected 2 meter temperatures today.
These expected temperatures will be around 10 degrees below normal.
Short term /6 PM this evening through 6 PM Friday/...
upper trough and shortwave energy pivot east later tonight and
Friday...replaced by a general flat northwest to southeast flow. Surface trough
extending from low pressure over the western Atlantic northwest across New
England will move to the north in time. Any lingering light
rain/snow showers or flurries/sprinkles tonight will end as the
focus for any convective development shifts north. Plenty of
clouds tonight will give way to clearing Friday.
As for temperatures...expect readings in the 20s tonight...and middle to upper
30s Friday per MOS.
Long term /Friday night through Wednesday/...
zonal flow this weekend will give way to Pacific northwest trough that
quickly moves across the northern states passing to the north
early next week. This will be followed by another trough that
moves out of the Pacific northwest...also tracking across northern states.
At the surface...high pressure over the area to start the period
moves east as the weekend progresses. A warm front then lifts across
the area Sunday...followed by a cold front Monday. As would be
expected...subtle timing and positional differences are noted in
the global models.
High pressure builds to the north during the latter portion of this
forecast as the front settles and stalls just to the south.
Temperatures gradually warm up this weekend into early next week. Then
temperatures fall behind the cold front Monday night/Tuesday. Little change
to previous forecast.
Aviation /15z Thursday through Monday/...
an upper level disturbance passes through today with a surface
trough nearby. High pressure builds in tonight.
Mostly MVFR...but only moderate confidence. VFR could prevail this
afternoon. MVFR could also prevail for a few more hours beyond
what is in the forecast.
Light snow or mixed rain and snow showers should be around through at
least middle afternoon. Precipitation not expected to be constant.
Winds primarily below 10 knots. Direction should favor north of 310
magnetic. Hover...at kewr...it probably favors south of 310
during the late afternoon.
Outlook for 12z Friday through Monday...
Sun-Mon...MVFR possible with a chance of rain and snow showers.
low pressure near Nova Scotia will move to the northeast as high pressure
builds to the west of the forecast waters. Although wind speeds are forecast
to remain below Small Craft Advisory levels...hazardous seas will gradually
subside into this evening. A Small Craft Advisory for hazardous seas
is in effect on the ocean waters.
On Friday the pressure gradient increases as the high builds closer
to the waters and a few gusts on the ocean waters may briefly approach
small craft once again.
Ocean seas out east could again reach marginal Small Craft Advisory levels Sat
night into Sunday night via a moderate SW flow. Small Craft Advisory level ocean
seas are also possible on Monday as southwest winds gust to 20-25 knots
ahead of a cold front.
no significant precipitation is expected over the next few days.
Marine...Small Craft Advisory for hazardous seas until 6 PM EST this
evening for anz355.
Small Craft Advisory for hazardous seas until 1 am EST Friday
short term...precipitable water
long term...precipitable water