Tonight:
Mostly cloudy, with a low around 42. South wind around 5 mph.
Tuesday:
A slight chance of rain showers after 2pm. Partly sunny, with a high near 60. Southwest wind 1 to 12 mph. Chance of precipitation is 20%.
Tuesday Night:
A slight chance of rain showers before 8pm. Partly cloudy, with a low around 40. West wind around 12 mph. Chance of precipitation is 20%.
Wednesday:
Mostly sunny, with a high near 52. Northwest wind 9 to 14 mph.
Wednesday Night:
Partly cloudy, with a low around 35. Northwest wind 7 to 12 mph.
Thursday:
Sunny, with a high near 49.
Thursday Night:
Partly cloudy, with a low around 32.
Friday:
Partly sunny, with a high near 50.
AREA FORECAST DISCUSSION
National Weather Service Mount Holly NJ
626 PM EDT Mon Oct 22 2018
Weather Synopsis:
High pressure will continue to move out to sea tonight, while a warm
front lifts north of the area. A cold front will move across the
area on Tuesday, then a surface trough crosses the area on
Wednesday. Northwesterly flow develops on Wednesday and Thursday,
before high pressure builds across the region Friday. A coastal low
will move northward near the East Coast over the weekend.
Near Term:
UNTIL 6 AM TUESDAY MORNING -
For the 630 PM update, increased the cloud cover some this evening
given a good amount of mid to high level cloudiness crossing about
the northern half of the area. Despite this, temperatures are
dropping off quite a bit so far in the more sheltered areas as the
winds diminish and dew points are on the low side. The hourly
temperature, dew point and wind grids were adjusted based on the
latest observations, then the LAMP guidance was blended in.
Otherwise, high pressure remains offshore while low pressure moves
across the upper Great Lakes region. An increasing southwest flow
will be over the area tonight, but this will be aloft as the lowest
levels will decouple through the overnight. Lows will be chilly but
not as cold as last night.
Short Term:
6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY -
Low pressure will move across NY and then New England Tuesday.
Clouds will increase over the area, but little precip is
expected. A small chc for showers was retained across nrn NJ and
into the southern Poconos. It will be mild, probably the
mildest day of the week, with highs in the mid/upper 50s N/W and
low/mid 60s for Philadelphia and other areas S/E. Winds will be
southwest at 10 to 15 mph.
Long Term:
TUESDAY NIGHT THROUGH MONDAY -
Behind the cold front Tuesday, a steady northwesterly flow
develops on Wednesday and Thursday as low pressure will be to
our northeast, and high pressure builds across the Great Lakes.
A weak surface trough may cross our area during the day
Wednesday as well. High pressure is then expected to build
toward our area on Thursday night, and across our area for
Friday. Mostly dry conditions are forecast for Wednesday through
Friday. The exception will be across portions of northeast
Pennsylvania and northern New Jersey where some light rain
shower/sprinkles, or even light snow showers/flurries will be
possible. A couple of short wave/vorticity impulses will move
across the area with some enhanced lift, along with enhanced
low-mid level lapse rates during the day Wednesday. Wednesday
and Thursday are expected to be breezy with wind gusts 15- 20
mph, but Friday will not be as windy with the high building
across the area.
The big questions with the long term comes with the potential
weekend coastal storm. There remains several different solutions
between the operations guidances and the ensemble guidance. The
GFS, GFS ensemble, and ECMWF ensemble keep the coastal storm
offshore of the Mid-Atlantic, while the ECMWF and Canadian bring
the low across the Delmarva and into eastern Pennsylvania and
New Jersey. We will continue with a forecast closer to the
ensemble means, which is similar to WPC as well. What this would
mean is that everyone has a chance of precipitation, with the
most likely areas along and south and east of the I-95 corridor
Friday nigh into Saturday. Most areas would be rain, although
there could be enough cold air for some mixing across northeast
Pennsylvania and northern New Jersey, especially Friday night.
Once this storm passes to the north, things get even more
convoluted with the pattern. Another low pressure system is
forecast to be moving across the Ohio Valley and into the Great
Lakes Saturday night into Sunday, while a frontal boundary lifts
across the area Sunday night with another low pressure
developing along this front near the area Sunday night into
Monday. This brings another chance of showers to the area, with
the potential for some lingering cold air across portions of
Northeast Pennsylvania and northern New Jersey which could lead
to some rain/snow mix again.
Click for full NWS PHI Office Area Forecast Discussion
