Area Forecast Discussion
Issued by NWS Mt. Holly, NJ
FXUS61 KPHI 310117
Area Forecast Discussion
National Weather Service Mount Holly NJ
917 PM EDT SAT JUL 30 2016
A weak frontal boundary will remain near our area into early next
week. A few weak low pressure systems will track along the
boundary, bringing periods of showers and thunderstorms. High
pressure will build across our area Tuesday into at least early
Thursday before moving off shore as a cold front approaches the
region the end of the week.
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
Flooding continues across portions of Mercer and Middlesex
counties where around 6 inches of rain has already been recorded.
Showers and thunderstorms continue to move across the region
tonight. With the boundary remaining in the area, we will continue
to see things firing up through tonight and into Sunday. The
latest runs of the HRRR and other model guidance gives confidence
to continuing showers and convection.
PW values are rather high, near 2 inches currently with a lot of
moisture streaming northward into the region. This will promote a
heavy rain and localized flooding threat with some of the showers
With plenty of clouds around and a southerly flow, temperatures
will stay warm overnight with lows in the 70s for most.
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
The frontal system will still be over the region through Sunday with
the main cold front moving southeast toward the region late in the
day. This will result in another round or two of scattered showers
and storms. The highest chances of showers and storms will be across
the northern portions of area, closer to the warm front. The initial
shortwave will be east of the area on Sunday, pulling in some
slightly drier air to the region. However, a lot of moisture will
remain in place leading to a threat of heavy rain with any
thunderstorms. Where more sun comes out across the southern half of
the region, highs have a good shot of reaching 90. Further north
with more clouds and thunderstorms, highs will be closer to 80.
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
Medium range models are fairly consistent bringing the mid level
trough across the region Sunday night through Monday night. Expect
enough instability, moisture, and lift associated with the broad
trough and embedded shortwaves for a continuation of the unsettled
weather. Pwats should still be in the 1.5-2 inch range at this
point so any storms could contain heavy rainfall. Expect residual
lingering boundaries to be the primary focus for any thunderstorm
As the trough moves east Tuesday, northwest flow overspreads the
region. A surface cold front will bring cooler temps, mainly in
the 80s, as well as drier air which will linger into at least
Model solutions begin to diverge at the end of the work week,
with the gfs showing a small but potent shortwave moving across
the forecast area. Despite the differences, multiple models show a
cold front moving across the region Friday night into Saturday.
Due to uncertainty in timing will include only low chance pops
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.
Showers and isolated thunderstorms this evening will reduce
ceilings and visibilities to MVFR/IFR at times. Showers will
likely occur throughout the nighttime hours. Ceilings will likely
lower throughout the night as well with MVFR/IFR ceilings and
visibilities currently expected toward or just after midnight.
Outside of thunderstorms, winds will generally be 10 knots or
On Sunday, Additional scattered showers and thunderstorms are
possible. However, a break or a period of lesser coverage is
possible in the late morning hours. Lower ceilings should lift by
late morning or early afternoon to VFR.
Sunday night through Monday night...Potential for MVFR ceilings
Monday morning, otherwise VFR with scattered to broken cloud
cover. Some showers and thunderstorms will be around especially
Sunday and this will lead to mainly local and brief restrictions.
Tuesday and Thursday...VFR overall as high pressure builds in.
Waveheights tonight will be around two feet with southeast winds
from 10-15 knots. Waveheights will increase some tomorrow pushing
four feet on the New Jersey coastal waters and around three feet
Sunday night through Thursday...An onshore flow Sunday should
increase some especially across the northern coastal waters, with
gusts to about 20 knots. It appears at this point that conditions
remain below advisory criteria. Otherwise, a weak pressure
gradient should keep winds and seas mainly below Small Craft
Advisory criteria through Thursday. Main concern will be the
threat of some thunderstorms Sunday and Monday, however the
greatest concentration of storms may be inland.
The rip current risk for Sunday is currently expected to be low.
However, with an increase in seas and winds on Sunday, a moderate
risk is possibile on the New Jersey coastline with a low risk
remaining in place further south where the increase will be less
with the seas.