Area Forecast Discussion
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FXUS61 KOKX 170525
Area Forecast Discussion
National Weather Service New York NY
1225 AM EST Tue Jan 17 2017
A warm front approaches late tonight and early Tuesday. Low
pressure passes Tuesday night. An active weather pattern will
continue into early next week with multiple frontal systems
impacting the area. In between each of these systems, high
pressure will be briefly build into the area.
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
The forecast is on track with no major changes made. Some light
rain near Hazleton may get into New Jersey zones by 4Z, but radar
returns are weakening. Will therefore handle with a Special
Weather Statement if the activity holds together and threatens a
quick shot of spotty light freezing rain.
Temperatures likely remaining fairly steady through the remainder
of the overnight.
The temperatures and onset of any precipitation will be the key
to the forecast as moisture ahead of upstream shortwave advects
eastward, along with weak lift.
Mainly west of NYC (NE NJ and west of the Hudson River), rain
will begin very late tonight, if not steady, but spotty. With
temperatures close to or just below freezing, light icing is
possible during the beginning of the morning commute for these
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
Mid and upper level ridge gives way to shortwave energy, PVA and mid
level lift by late in the day and through the evening. At the
surface, weak high pressure moves well to the east as a warm front
approaches late in the day. It looks like triple point low pressure
develops near the NYC metro in the evening and passes east at night,
hugging the coast. Deep moisture by late in the day and through the
evening will result in a steady rain.
Once again, interior portions of the area in the morning may be cold
enough for an increasing area of rain/freezing rain as temperatures
hover around the freezing mark before warming. A freezing rain
advisory has been posted for these locations for the morning hours.
As the low passes Tuesday night and mid and high level moisture
moves east, lift weakens and any rain will lighten, taper off and
become more intermittent. Patchy fog at night is expected with
light flow, cooling temps and abundant low level moisture.
Temperatures rise into the upper 30s and lower 40s during the
afternoon, then fall back a few degrees at night.
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
Southern branch of the polar jet will continue to be the main
player during this period with multiple Pacific frontal systems
impacting the area. Global models are in overall good agreement
with some timing differences. During this time, temperatures will
remain above seasonable levels with high generally in the 40s and
lows in the 30s.
Each of the aforementioned frontal systems looks to interact with
an airmass that supports primarily rain. The first system will
pass to the east Wednesday morning with rain tapering off from
west to east. High pressure then follows Thursday into Friday
before another southern branch system brings rain to the area.
The 12Z operational GFS is stronger with high pressure over
eastern Canada with the passage of a northern branch shortwave
trof. This scenario would have a somewhat colder airmass in place
for Saturday`s event, but model consensus points toward weaker
high pressure. Thus, for the time will keep out any mention of
freezing rain across the interior. Vertically the airmass would
be warm enough for rain. Early next week, another system impacts
None of the short term climate predictors show much change in the
upper flow through next week. Thus, wet and warm looks to be the
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
A warm front slowly approaches from the southwest today, with low
pressure developing to the south of New York City by late this
VFR through 9z and probably through at least 13z. However, there is
a low chance of rain or freezing rain moving into western terminals
9-12z with MVFR ceilings. MVFR conditions develop mid-late morning
morning at western terminals, with freezing rain at KSWF.
Precipitation changes to all rain by early afternoon and moves into
eastern terminals, along with MVFR conditions. IFR conditions then
develop from W to E through the afternoon and continue through the
TAF period. There is a chance that conditions could fall to
LIFR/VLIFR this evening.
Winds become light and variable throughout early this morning. E-SE
winds at under 10kt develop at mainly coastal terminals this
afternoon, then back to the E-NE this evening, with winds at inland
terminals staying mainly light and variable.
.OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...
.Late Tuesday night-Wednesday...MVFR/IFR likely, with LIFR
possible, in rain.
.Wednesday night...Becoming VFR.
.Friday night-Saturday...Chance of MVFR or lower. E-NE winds G15-
As high pressure departs, westerly winds will persist, but
remain under 15 KTs tonight. A warm front and low pressure will
approach the waters Tuesday, and pass over the waters Tuesday night.
Winds turn to the east ahead of the front and low during the day
Tuesday, then will vary based on location before becoming NW
late Tuesday night.
With winds remaining rather light through Tuesday night, expect
seas to remain 3 ft or less on the ocean, and 1 ft or less across
the non ocean waters.
Winds on the ocean may approach 20 kt on the ocean late Wednesday
into Wednesday night as low pressure gradually intensifies
offshore. The low will slowly move to the east Thursday into
Friday. Ocean seas should stay below SCA levels, but could
approach 4 ft the end of the week. Otherwise, a weak pressure
gradient continues to bring Sub-SCA winds on all waters for the
end of the week.
No hydrologic impacts are anticipated with around a half inch of
precipitation Tuesday through early Wednesday.
The best chance for significant precipitation looks to be early next
week as a potential strong southern branch upper trough
approaches the region.
CT...Freezing Rain Advisory from 7 AM this morning to noon EST
today for CTZ005.
NY...Freezing Rain Advisory from 7 AM this morning to noon EST
today for NYZ068.
Freezing Rain Advisory from 4 AM early this morning to noon
EST today for NYZ067.
NJ...Freezing Rain Advisory from 4 AM early this morning to noon
EST today for NJZ002.