Marine Weather and Tides
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|Sunrise 6:51AM||Sunset 6:54PM||Tuesday September 25, 2018 9:26 AM EDT (13:26 UTC)||Moonrise 6:36PM||Moonset 6:10AM||Illumination 99%|
7 Day Forecast for Marine Location Near Trexler, PAHourly EDIT Help
Area Discussion for - Philadelphia/Mount Holly, PA  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus61 kphi 251016|
area forecast discussion
national weather service mount holly nj
616 am edt Tue sep 25 2018
A warm front is expected to lift north through the region today. It
will be quickly followed by a cold front late tomorrow or tomorrow
night. A large area of high pressure will gradually build east
towards the region and eventually off shore through early next week.
A weak cold front should arrive in the area late this weekend,
followed by another warm front on Monday.
Near term until 6 pm this evening
High pressure across new england will move away today while a
warm front approaches from the south. A moist circulation off
the ocean will keep plenty of clouds across the area today. The
front will add enough lift to trigger frequent showers N W early
today and then across most areas later this morning. By
afternoon, the showers will move northward bringing the
opportunity for some breaks over DELMARVA and SRN nj.
Temperatures will remain mostly in the 60s across the north and
in the mid upper 70s over the delaware valley and much of nj.
It's possible that some low 80s could be realized if the sun
returns earlier than expected. Winds will be mostly E SE this
morning and then turn srly this afternoon.
Short term 6 pm this evening through 6 am Wednesday
The ill-defined warm front will be crossing the area tonight.
Winds will remain southerly or turn a little swrly after is
passes through. Warm and humid air will be across the area
overnight. There will be some showers across the northern areas
early tonight, but overall, most areas will only see scattered
showers. Lows tonight will only drop into the mid 60s across the
north and low 70s over DELMARVA and SRN nj.
Long term Wednesday through Monday
Summary: the main period of concern is Wednesday into Wednesday
evening as there is a risk of strong to severe thunderstorms
ahead of the cold front. After that, the weather pattern should
be relatively quiet until we get to early next week when another
round of precipitation is possible primarily from Monday into
Wednesday and Wednesday night... The models are coming into
better agreement of the cold frontal passage generally through
the evening and overnight hours. Ahead of this front, expect
more than sufficient lift and instability for a period of
thunderstorms. As for the thunderstorm hazards:
heavy rain... Precipitable water values are, no surprise,
expected to be well above normal. However, storm motions will be
fast, likely 30 mph or more. So while the storms may be
efficient rain producers, the threat for flooding is limited.
This is assuming however, that the front will be as progressive
as currently expected. If the progress slows, there is some
potential for training storms which would once again increase
the threat for heavy rain.
Severe storms... The threat for severe thunderstorms is
conditional on the timing of the front. If the front arrives
late at night, instability will be more limited and thus the
threat for severe will be limited. Models seem to be converging
on the evening into overnight timing, so it does look like there
will be at least a slight risk of severe storms across our
area. As has been the case with almost all of our convection
this summer, NAM model soundings are significantly more unstable
than other guidance. Forecast CAPE values, even going with the
more stable GFS model soundings, are more than enough for tall
updrafts. While the highest values of 0 to 6 km shear will be to
our north, shear over our area should still be sufficient for
persistent enough updrafts to support some severe threat. The
primary hazard looks to be strong winds as this looks like a
qlcs pattern. The low level shear, at least in our area, doesn't
look high enough for a significant tornado threat, but we will
continue to watch this closely. Finally with hail, while some
small hail is possible, the CAPE profiles in the hail growth
layer are rather thin, so the threat for severe hail looks to be
Thursday and Friday... Once the front is south of our area, it
may stall, though there remains some uncertainty with just how
far south it will be before it stalls. A pair of weak lows are
expected to propagate along the front through the early weekend.
Depending on how far south the front is, we could see some of
the wrap around precipitation in our area through this time.
Given the uncertainty though, stayed close to the previous
forecast, with the main chances on Thursday night.
Saturday through Tuesday... .A weak cold front is expected to
pass through Saturday or Sunday (considerable timing differences
between the models), but without any southerly return flow
setting up ahead of the front, expect this to be a dry frontal
passage. Monday into Tuesday, a low should be lifting out of the
great plains into the great lakes region, depending on how far
east the track is, we could see a warm front lift through the
region during this time.
Aviation 10z Tuesday through Saturday
The following discussion is for kphl, kpne, kttn, kabe, krdg,
kilg, kmiv, kacy and surrounding areas.
Today... Poor flying conditions much of today as a warm front affects
the area. Mostly MVFR with the possibility for some ifr for much of|
the morning. Frequent rains showers will affect N W terminals before
dawn, then fill in across most areas for the rest of the morning.
Improvement will take place from S to N late this morning and into
the afternoon with a return toVFR in most areas. Sct showers could
still bring lower conditions however. Winds mostly E SE through the
morning and then S for the afternoon.
Tonight... Rather low confid fcst with a continuation of deep srly
flow across the area. CIGS will probably decrease to MVFR, but the
areal extent of any showers is not certain. Some of the NAM guidance
is showing that ifr is possible. Mostly S winds around 10 knots
Wednesday and Wednesday night... Periods of MVFR and even ifr
conditions are possible with showers and thunderstorms along and
ahead of a cold front. The storms and front will be progressing
from west to east. The prime period for any thunderstorms at
the TAF sites should be between 18 and 03z, with a shift to
northwesterly winds coming just behind the storms, and a shift
to northerly winds coming after 06z. Gusty winds will be
possible in the vicinity of any storms and for a brief period
behind the front. Moderate confidence.
Thursday through Sunday... MostlyVFR conditions expected. There
is a chance for showers on Thursday night which could result in
lower conditions. Winds should be light and variable through
the period. Moderate confidence.
It appears that the SCA conditions across delaware bay may
last a bit later than earlier expected. We'll extend the SCA flag
until 15z for now. Decent E to SE flow is keeping sustained winds 15
to 20 knots with gusts 25 to 30 kts across the waters early today.
Sca conditions on the ocean today and tonight with winds decreasing,
but seas remaining above 5 ft. Showers much of the morning, ending
from S to n.
Wednesday... On the ocean waters, SCA conditions, in the form of
elevated seas, continue. On the delaware bay, winds and seas should
stay below SCA criteria. However, gusts above 34 kt may be possible
in the vicinity of any thunderstorms.
Wednesday night and Thursday... An abrupt shift to northwesterly
winds is expected with a cold front Wednesday evening into late
Wednesday night. A period of gusts to 25 kt is possible just behind
the front, however confidence is low at this time. On the ocean
waters, seas should be diminishing through this time, but may stay
at or above 5 feet for much of the period. The SCA may need to be
extended further if confidence increases.
Friday through Sunday... Winds and seas should stay below sca
moderate risk for the development of dangerous rip currents.
Tides coastal flooding
Water levels now that we are approaching low tide on the
oceanfront and lower delaware bay are running higher than
guidance. Consequently, think we will have compounding issues
for the next high tide cycle later this morning. Thus, the
coastal flood advisory continues for areas along the ocean
front, the delaware bay, and the tidal delaware river. Back bays
may be especially vulnerable with this next high tide cycle as
there will be little chance for water to drain before then. At
this point though, no gauge is expected to be higher than minor
On the chesapeake bay, spotty minor flooding is occuring with
this morning's high tide, but water levels are expected to stay
below advisory thresholds. However, with increasing southerly
flow through the day, expect higher anomalies with the high tide
this evening. Therefore, have issued a coastal flood advisory
for northeastern maryland.
Phi watches warnings advisories
Pa... Coastal flood advisory until 5 pm edt this afternoon for
Nj... Coastal flood advisory until 2 pm edt this afternoon for
Coastal flood advisory until 5 pm edt this afternoon for
De... Coastal flood advisory until 2 pm edt this afternoon for
Md... Coastal flood advisory from 4 pm this afternoon to midnight
edt tonight for mdz008-012-015-019-020.
Marine... Small craft advisory until 6 am edt Thursday for anz450>455.
Small craft advisory until 10 am edt this morning for anz430-
near term... O'hara
short term... O'hara
long term... Johnson
aviation... Johnson o'hara
marine... Johnson o'hara
tides coastal flooding... Johnson
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|PHBP1 - 8545240 - Philadelphia, PA||53 mi||45 min||67°F||69°F||1024.6 hPa|
|BDRN4 - 8539094 - Burlington, Delaware River, NJ||54 mi||51 min||65°F||66°F||1025.4 hPa|
Wind History for Philadelphia, PA(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Allentown Queen City Municipal Airport, PA||8 mi||52 min||NE 6||4.00 mi||Heavy Rain||0°F||0°F||%||1026.7 hPa|
|Allentown, Lehigh Valley International Airport, PA||12 mi||36 min||NE 6||2.00 mi||Light Rain Fog/Mist||58°F||55°F||90%||1026.3 hPa|
|Quakertown Airport, PA||18 mi||32 min||Var 3||3.00 mi||Fog/Mist||59°F||59°F||100%||1026.1 hPa|
|Reading, Reading Regional Airport, PA||23 mi||33 min||N 5||3.00 mi||Light Rain Fog/Mist||59°F||59°F||100%||1025.8 hPa|
Wind History from XLL (wind in knots)
|1 day ago||N||NE||NE||N||NE||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||NE||NE||N||N||NE||NE||NE||NE||NE||NE|
|2 days ago||N|
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Wind Forecast for Philadelphia/Mount Holly, PA (9,2,3,4)(on/off)  Help
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