Scientific Forecaster Discussion
fxus61 kphi 240722
Area forecast discussion
National Weather Service Mount Holly New Jersey
322 am EDT Sat Aug 24 2019
high pressure across the upper Great Lakes region this morning
will continue to move east across southern Canada today and
tonight. The high will try to spread down the East Coast, but
not fully make it into the area. The high will retreat north and
east next Tuesday and Wednesday. This will allow an area of low
pressure to lift northward off the eastern Seaboard during the
mid week period and a cold front to track through the area
later next week.
Near term /through today/...
a trough of low pressure will remain aloft while a surface high
pressure area moves across southern Canada today. This will
bring more cooler and drier air from the north into our region.
We'll see more sunshine than Friday, so highs will be 4 to 6
degrees warmer that yesterday, but highs will be below normal
for mid-late August. Readings will top out in the low/mid 70s
north/west and close to 80 across southeast PA, south New Jersey and Delmarva. Winds
will be mostly north to NE at 5 to 10 mph this morning and the NE to
east at 10 to 15 mph this afternoon. Some mid/high level clouds
will move across the srn areas this morning and into the
afternoon, but overall a nice day expected.
Short term /tonight/...
high pressure will continue to strengthen while it moves to
ME/srn Quebec. This will bring an increasing NE to east flow across
our area and could result in some increasing low clouds and
perhaps some light rains near the coast towards daybreak Sunday.
We have kept the slight chc pops and increased the clouds for
these areas. Low will be cool with readings dropping into the
mid/upper 50s north/west and over The Pine Barrens of New Jersey. Elsewhere,
readings will be in the 60s with mid/upper 60s near the shore
with the nearby warmer waters. Winds will be NE to east at 5 to 10 mph.
The winds will be higher near the shore with 10 to 15 mph more
Long term /Sunday through Friday/...
this long term section will be updated shortly.
Cooler conditions everywhere with small pops across the coastal
plain will start the long term period. An increase in temperatures
and greater chances of precipitation will return by the middle of
next week and persist through late week.
As we move into Sunday and Monday, the easterly flow will
continue as high pressure builds a little farther southward
across New England. The high will try to nose its way down the
east coat toward the mid Atlantic region during this time as
well. Guidance continues to indicate precipitation developing
across the area during this period, so we will have a slight
chance/chance of showers Sunday through Monday. However, it may
just end up being more cloudy rather than rainy as some
stratocumulus clouds could develop with the persistent easterly
flow. Regardless, if it does rain, it is expected to be light as
precipitable water values are mostly an inch or less.
As we move into Tuesday through Thursday, unsettled weather could
return to the area. An area of low pressure is forecast to be
lifting northward off the East Coast Tuesday through Thursday. At
the same time, a cold front is expected to approach from the west
during the day Wednesday into Thursday. There are some timing
differences with these systems. However, there will be an increasing
chance of showers and thunderstorms starting Tuesday and continuing
With the region expected to be behind the cold front on Friday,
precipitation chances will be on the decline. Little temperature
change is expected at the moment behind the front.
Aviation /05z Saturday through Wednesday/...
today...VFR expected. North winds 5 to 10 knots early, then NE 8 to
12 knots late morning and into the afternoon. Some gusts close
to 20 knots near kacy late morning and afternoon. Sct-bkn
050-060 kmiv/kacy this afternoon.
Tonight..VFR continues. Low clouds possible late near the shore
towards dawn Sunday. Confid is not high enough to include in
tafs attm. East winds 5 to 10 knots.
Sunday...mainly VFR conditions expected. MVFR conditions possible at
kacy and kmiv as an onshore flow generates some clouds/drizzle/light
rain. Low confidence. NE winds 5-10 kts with gusts up to 20 knots
Sunday night-Tuesday...more widespread MVFR conditions developing
with the persistent onshore flow. East to NE winds 5-10 kts with gusts
up to 20 kts possible.
Wednesday...mainly VFR as the onshore loses its grip across the
region. Winds less than 10 kts.
high pressure moving north of the waters today and tonight will cause
winds to be mostly north or NE today and then NE to east tonight. Winds
and seas will slowly increase to near Small Craft Advisory conditions for awhile
both this afternoon and late tonight. Not really expecting the Small Craft Advisory
conditions to persist too long with only perhaps a gust or two and
a few seas nearing 5 ft. We'll hold on the Small Craft Advisory flag for now, although
a short term Small Craft Advisory is possible later. Fair weather today and a slight
chc for a shower late tonight.
Sunday-Wednesday...a prolonged low end Small Craft Advisory may be needed through
the period as long fetch east to NE winds persist.
Increasing northeasterly winds and seas building to around 4 ft
by the afternoon will result in a moderate risk of rip currents
This elevated rip current risk (either moderate or at times
high) is expected to persist beyond Saturday until at least
Tuesday as a prolonged period of onshore flow and elevated seas
a prolonged northeast to east flow is expected today through at
least Tuesday. This persistent onshore fetch, combined with increasing
astronomical tides due to an approaching new moon on Thursday will
likely lead to increasing coastal water levels. Guidance is already
indicating that minor coastal flooding is becoming more likely Monday
and Tuesday over Delaware Bay and portions of the New Jersey shore.