Wednesday, January23, 2019 L-36.com


Marine Weather and Tides
Croydon, PA

Version 3.4
What's New / NOTES
10/6/2018 Colors of tide XTide graphs changed to emphasize that they were upgraded. See next note. Comments welcome.
10/4/2018 I have fixed XTide and updated the harmonic files. There were some name changes so you might have to click EDIT to find the new station name.

Sunrise 7:13AMSunset 5:08PM Wednesday January 23, 2019 12:26 PM EST (17:26 UTC) Moonrise 9:20PMMoonset 10:09AM Illumination 92% Phase: Waning Gibbous; Moon at 17 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
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ANZ338 NEw York Harbor- 1016 Am Est Wed Jan 23 2019
.small craft advisory in effect from 6 pm est this evening through Thursday afternoon...
This afternoon..S winds 5 to 10 kt. Waves 1 ft or less.
Tonight..S winds 10 to 15 kt, increasing to 15 to 20 kt after midnight. Gusts up to 30 kt. Waves building to 2 to 3 ft. Chance of rain in the evening, then rain after midnight with vsby 1 to 3 nm.
Thu..S winds 15 to 20 kt, becoming W in the afternoon. Gusts up to 30 kt. Waves 2 to 3 ft. Rain, mainly in the morning. Vsby 1 to 3 nm.
Thu night..W winds 10 to 15 kt with gusts up to 25 kt. Waves 1 to 2 ft.
Fri..W winds 10 to 15 kt with gusts up to 25 kt. Waves 1 to 2 ft.
Fri night..W winds 10 to 15 kt. Waves 1 to 2 ft.
Sat..W winds 5 to 10 kt. Waves 1 ft or less.
Sat night..SE winds 5 to 10 kt. Waves 1 ft or less.
Sun..SE winds 5 to 10 kt, increasing to 10 to 15 kt in the afternoon. Waves building to around 2 ft. Chance of snow showers. Vsby 1 to 3 nm.
Sun night..S winds 5 to 10 kt, becoming W after midnight. Waves 1 ft or less. Chance of snow showers in the evening. Vsby 1 to 3 nm.
ANZ300 1016 Am Est Wed Jan 23 2019
Synopsis for the long island waters and new york harbor.. A cold front will approach from the west into tonight with a wave of low pressure riding along it to our north Thursday morning. The low will drag the cold front across the region Thursday afternoon. High pressure will then build into the region Thursday night and remain nearby through Saturday. A cold front will approach and move across the area on Sunday.


7 Day Forecast for Marine Location Near Croydon, PA
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location: 40.08, -74.88     debug


Area Discussion for - Philadelphia/Mount Holly, PA
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Fxus61 kphi 231422
afdphi
area forecast discussion
national weather service mount holly nj
922 am est Wed jan 23 2019

Synopsis
An area of low pressure will move northeastward from the great lakes
into quebec through Thursday. A warm front will cross our region
today and tonight, followed by a cold front Thursday. High pressure
will then build into the region Friday and Saturday. A developing
area of low pressure to our northwest will pull a cold front through
our region Sunday, with a coastal low potentially developing along
this front early next week.

Near term through tonight
For the 930 am update, refreshed the hourly grids to reflect the
current obs then blended into continuity. No significant changes
were needed to these at this time. Delayed the start time a little
of the measurable pops. The precipitation shield is currently in
western pennsylvania, however some light and perhaps spotty
precipitation may start to develop in the pocono region toward
midday. Looks like any precipitation would be light given weak
forcing despite the ongoing warm air advection. Speaking of warm air
advection, an analysis already shows the leading edge of the warm
layer (above 32f) centered near 850 mb is north of our region. The
12z sterling, va and upton, ny roabs confirm this. The warming is
being propelled by an increasing low-level jet, which is at 60 knots
at 925 mb via the sterling, va raob. This will continue to drive
warming northward, and the surface temperatures will eventually
catch up as some mixing develops by later today as the boundary
layer warms (especially in the coastal plain). No other changes were
made, for now.

Otherwise, the concern in the forecast today lies with the freezing
rain drizzle potential across the northern portion of the cwa. The
nam has a stronger signal for this to occur, whereas the GFS is a
bit warmer drier. Not overly confident of what will end up
transpiring. The large-scale lift associated with a subtle midlevel
perturbation moving through the region during the day is weak, at
best, and there are some questions as to how quickly the low levels
will moisten sufficiently for any precipitation to occur. Bufkit
soundings are quite variable model to model, and the overall
appearance of the more aggressive models is for (near-)saturation
generally at below the 700-mb level. This suggests any precipitation
will be light and liquid. Would not be surprised if little more than
drizzle occurs northwest of the fall line through the day given the
shallow look of the moist profiles and the rather dry near-surface
layer. Of course, the other question will be surface temperatures,
with statistical guidance appearing much too warm much too quickly.

The typically colder NAM (raw) model output was favored here, which
slows the warming temperatures north of i-78 considerably during the
day. So far, this has worked well for temperatures early this
morning in these areas (especially the poconos and far northern new
jersey).

With the above in mind, have slight chance to low chance for (light)
freezing rain starting late this morning. It doesn't appear that
this will make it further south than the lehigh valley at this
point, as surface temps will likely be above freezing by the onset
of precipitation southeast of the fall line. The window for near-
freezing temperatures in the lehigh valley is quite short, with
temperatures well above freezing likely by mid afternoon. The best
potential for a longer duration of near-freezing temperatures
remains in carbon and monroe counties, where a winter weather
advisory is already in effect. Confidence is too low for expansion
elsewhere given questions regarding precipitation coverage, onset
versus marginal (and warming) surface temperatures, and overall
model variability.

Tonight the main forecast question is how quickly the steadier rain
moves into the area, with overall consensus suggesting a slower
onset. Generally, increased pops from northwest to southeast through
the period, with timing matching a consensus hi-res blend. The main
period of precipitation looks to start after midnight, possibly
reaching the atlantic coast as late as daybreak.

Kept temps on the colder side for today's highs, given the cold air
over the past couple days, and the overall tendency for it to stick
around in these scenarios longer than simulated. Also, bumped temps
up a touch across DELMARVA to account for the stronger warm air
advection trend through the day. As it stands, highs should range
from the mid 30s across the poconos to the low 50s across southern
delaware. Winds will pick up through the day, with gusts above 25
knots possible along the coast and over DELMARVA by evening. Given
the southerly flow and warm air advection, lows Wednesday night will
likely not deviate much from Wednesday's highs, with a warming trend
possible through the period.

Another sensible weather impact of note tonight will be the
increasing south to southeast winds generally southeast of the urban
corridor. Winds may gust 30 to 35 mph in this area (possibly
stronger near the coast) as a strong low-level jet develops aloft.

Though mixing will not be efficient, it may be strong enough to
generate some rather breezy conditions overnight.

Short term Thursday through Thursday night
Strong surface low in quebec 12z Thursday will lift northeast
through the day, dragging a cold front through the region. Very
strong southerly southwesterly low-level flow in advance of the
front will continue to advect warm and unusually moist air into the
area. Forecast pws approach 1.5 inches during the morning, which is
in record territory climatologically. Additionally, very strong and
deep ascent aided by favorable positioning of the right entrance
region of an intense 250-mb jet streak, considerable differential
cyclonic vorticity advection, and low-level isentropic ascent aided
by a 70-kt synoptically-forced low=level jet will generate
widespread precipitation across the mid-atlantic during the morning.

Bufkit soundings show very weak instability in advance of the front,
so little or no lightning is expected (except maybe off the coast).

Nevertheless, strong frontal lift appears to generate sufficient
lift for locally intense enhanced precipitation. With the high-
octane air in place, a period of heavy rain is probable in advance
of the front. Model QPF is generally 1 to 1.5 inches from 09z to 21z
across the area, with most of this precipitation likely occurring in
a 3-6 hour period at any particular location. With cold soils,
months of antecedent wet conditions, and relatively high rain rates
expected at times during the day, flooding potential seems elevated.

Have issued a flood watch for the lehigh valley southeastward to the
i-95 295 corridors for Thursday. Though the watch is technically an
areal flood watch, flash flood potential exists here, given the
possibility of high rain rates producing quick rises in sensitive
streams and urban areas. For more information, see the hydrology
section below.

Winds will also be elevated in advance of the front, aided by the
aforementioned low-level jet and sufficient mixing. Additionally,
any convectively-induced precipitation may mix down some very strong
winds aloft. Will need to watch this potential closely as the event
unfolds.

The front races offshore during the afternoon, with precipitation
potential rapidly lowering behind it. Cold air will filter in
quickly. Depending on how quickly the precipitation ceases upstream
of the front, may see a quick brief switchover to snow showers
before the precipitation ends, especially in the northwest cwa.

Temperatures will surge in advance of the front, with readings in
the 50s to near 60 southeast of the fall line. However, temperatures
will fall rapidly behind the front, with lows below freezing
virtually everywhere Thursday night. Skies should rapidly clear by
Thursday night, although some lingering moisture may keep the low
clouds present in the far northwestern cwa. Cannot rule out a few
flurries here as low-level northwest flow develops and a weak
perturbation approaches the northern mid-atlantic overnight.

Long term Friday through Tuesday
Following the system, mainly dry but colder conditions move back in
for Friday lasting through Saturday as the next high moves in.

Temperatures will be slightly below average, but still an
improvement to what we have seen the past couple days.

Lots of uncertainty in this period. In the big picture, a long wave
trough will remain present over eastern north america with a closed
low at 500 mb persisting around hudson bay. The pattern looks to
remain active with several potent pieces of energy moving
southward eastward around this trough towards the coast, potentially
phasing with southern stream energy. An area of low pressure looks
to develop across the great lakes as several of these pockets of
energy associated with shortwave troughs phase by Sunday. This keeps
precipitation in the forecast through the weekend and into the
middle part of next week. This will start as snow showers across the
poconos and likely build southeast across the CWA Sunday. The chance
for snow and rain showers could last really through the middle part
of next week. Still considerable uncertainty in how much moisture
will be available and how things will come together. Kept a slight
chance of rain showers (south) and snow showers (north) in the
forecast through Wednesday. Temperatures remain cold with highs
slightly below average through the beginning of the week. Wednesday
looks to be quite chilly with highs remaining below freezing across
much of the forecast area.

Aviation 15z Wednesday through Sunday
The following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.

Today... GenerallyVFR, though CIGS will be lowering and may
reach sub-vfr thresholds northwest of philly by mid to late
afternoon. Cannot rule out some drizzle or light rain at rdg abe
as well. Additionally, a low-cloud deck is approaching the area
from the south and may produce lowVFR or even briefly MVFR
cigs near south of phl this morning. Winds generally south
around 10 kts. Llws increases from the southwest rapidly this
afternoon. Low confidence.

Tonight... Conditions will be deteriorating gradually to sub-vfr
and may reach ifr or worse near after midnight. Rain chances
increase from northwest to southeast, especially after midnight.

Winds south around 10 to 15 kts, possibly gusty near southeast
of phl. Southwesterly llws anticipated through the night.

Moderate confidence.

Thursday... Cig vsby restrictions will continue through at least
early afternoon, with rain (heavy at times). Southwesterly llws will
also continue through the morning. Conditions are expected to
improve rapidly during the afternoon, withVFR possible late.

Southwest winds 10 to 20 kts with higher gusts before frontal
passage, becoming northwest afterward. Moderate confidence.

Thursday night... MainlyVFR with west to northwest winds around or
below 10 kts. Moderate confidence.

Outlook...

Friday and Saturday... MainlyVFR conditions expected. Winds
generally below 20 knots. High confidence.

Saturday night through Sunday night... Cold front may bring rain
and or snow showers, thus possibly lowering visibilities and
bringing restrictions, especially at krdg and kabe. Moderate
confidence.

Marine
Sub-advisory conditions exist on the waters at this time, but south
to southwest winds are already increasing off the new jersey coast.

Winds are expected to reach advisory levels later this morning, so
have moved up the start time of the small craft advisory to 6 am on
the atlantic waters. Conditions should remain sub-advisory on
delaware bay through the day.

Conditions will deteriorate further tonight, as south to southwest
winds strengthen to 20 to 25 kts with gusts to at least 30 kts.

Gales cannot be ruled out, especially on the atlantic waters, though
low-level temperature profiles are not climatologically favorable
for their development. As such, did not issue a gale watch at this
time. Conditions will worsen on delaware bay, and the small craft
advisory remains in effect overnight.

Seas on the atlantic will increase to 5 to 10 feet tonight.

Outlook...

Thursday: small craft advisory in effect, and gales are
possible. Seas 5 to 10+ feet. A cold front moves through during
the afternoon, with winds switching from south or southwest to
northwest. Rain likely, with visibility restrictions probable.

Cannot rule out thunder, but confidence was not high enough to
include in the forecast.

Thursday night: rain moves out, and northwest winds diminish but
will likely remain above advisory criteria much of the night. Seas
will also remain elevated but will lower as the night progresses.

Small craft advisory was extended through 4 am Friday for delaware
bay and through 6 am for the atlantic waters.

Friday and Saturday... Sub-sca conditions expected with westerly
winds 10-15 knots. Seas from 4-6 feet.

Saturday night through Sunday night... Sub-sca conditions
expected with easterly winds initially, turning southwesterly
from 10-15 knots. Seas from 3-5 feet.

Hydrology
We have issued a flood watch for late tonight through Thursday
afternoon from the lehigh valley and northwest new jersey
southeastward to the i-95 295 corridors. A cold front will move
through the area on Thursday, with a round of rain, moderate to
heavy at times, expected to move through the region in advance of
the front late tonight into tomorrow morning. Expected storm totals
are generally from 1 to 1.5 inches, with locally higher amounts
possible. Normally, these totals would not be forecast to produce
much flooding. However, a number of factors suggest an elevated
threat exists...

1) antecedent wet conditions, including from the rainfall this past
weekend.

2) relatively cold soils, aided by the arctic air that spread across
the region the past couple of days.

3) the expectation of most of this rain occurring in a three-to-six
hour period. With higher rain rates expected during a portion of the
event, especially just in advance of the frontal passage on
Thursday, additional runoff will be generated, which could lead to
flooding of particularly sensitive spots (e.G., urban areas and
quickly-responding creeks and streams).

4) light to moderate rain occurring for a few hours before the
heaviest rainfall occurs, which may act to saturate soils
sufficiently for efficient runoff during the most intense rainfall.

An isolated instance of flash flooding is possible, especially if
the heaviest rainfall (and high rainfall rates) occurs along the
urban corridor or atop smaller stream creek basins that respond
rapidly to runoff.

River flooding cannot be ruled out, especially on the passaic and
millstone rivers, if the axis of heaviest rainfall intersects the
associated basins.

Phi watches warnings advisories
Pa... Flood watch from late tonight through Thursday afternoon for
paz061-062-070-071-101>106.

Winter weather advisory until 5 pm est this afternoon for
paz054-055.

Nj... Flood watch from late tonight through Thursday afternoon for
njz001-007>010-012>020-026-027.

De... Flood watch from late tonight through Thursday afternoon for
dez001.

Md... Flood watch from late tonight through Thursday afternoon for
mdz008.

Marine... Small craft advisory until 6 am est Friday for anz450>455.

Small craft advisory from 6 pm this evening to 4 am est Friday
for anz430-431.

Synopsis... Davis
near term... Cms gorse
short term... Cms
long term... Davis
aviation... Cms davis
marine... Cms davis
hydrology... Cms


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
BDRN4 - 8539094 - Burlington, Delaware River, NJ 1 mi51 min SW 7 G 11 38°F 32°F1025.1 hPa
NBLP1 - 8548989 - Newbold, PA 8 mi39 min SW 7 G 11 38°F 32°F1025.6 hPa
BDSP1 13 mi39 min 38°F 35°F1025.1 hPa
PHBP1 - 8545240 - Philadelphia, PA 17 mi39 min 1024.7 hPa
MRCP1 - 8540433 - Marcus Hook, PA 34 mi45 min 36°F 34°F1025 hPa
JCRN4 - Jacques Cousteau Reserve, NJ 44 mi57 min S 8 44°F 1026 hPa22°F

Wind History for Burlington, Delaware River, NJ
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Philadelphia, Northeast Philadelphia Airport, PA7 mi33 minSW 1010.00 miOvercast42°F19°F41%1025.4 hPa
Mount Holly, South Jersey Regional Airport, NJ9 mi33 minSSW 410.00 miOvercast41°F21°F47%1025.2 hPa
Trenton, Mercer County Airport, NJ14 mi34 minSSW 910.00 miOvercast39°F21°F48%1024.3 hPa
Mcguire Air Force Base, NJ15 mi31 minSW 1010.00 miOvercast41°F21°F44%1024.1 hPa
Doylestown, Doylestown Airport, PA21 mi33 minSSE 510.00 miOvercast36°F19°F50%1024.4 hPa
Philadelphia - Wings Field Airport, PA21 mi32 minS 10 G 1410.00 miOvercast37°F24°F60%1024.7 hPa
Philadelphia, Philadelphia International Airport, PA24 mi33 minSW 9 G 1810.00 miOvercast40°F21°F49%1025.2 hPa

Wind History from PNE (wind in knots)
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Last 24hrNW33CalmCalmS3S3CalmS3Calm33S5S43S6S5S4S4S3S6SW6SW8SW9SW10
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Tide / Current Tables for Burlington, New Jersey
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Burlington
Click for Map
Wed -- 03:47 AM EST     7.15 feet High Tide
Wed -- 07:15 AM EST     Sunrise
Wed -- 09:08 AM EST     Moonset
Wed -- 11:10 AM EST     -0.62 feet Low Tide
Wed -- 04:07 PM EST     8.30 feet High Tide
Wed -- 05:07 PM EST     Sunset
Wed -- 08:19 PM EST     Moonrise
Wed -- 11:48 PM EST     -0.76 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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0.63.25.36.77.16.45.242.91.60.3-0.60.235.77.58.37.96.75.44.22.91.4-0.2

Tide / Current Tables for Philadelphia, Pennsylvania Current
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Philadelphia
Click for Map
Wed -- 12:34 AM EST     2.12 knots Max Flood
Wed -- 03:35 AM EST     -0.00 knots Slack
Wed -- 06:44 AM EST     -2.24 knots Max Ebb
Wed -- 07:16 AM EST     Sunrise
Wed -- 09:09 AM EST     Moonset
Wed -- 10:31 AM EST     0.00 knots Slack
Wed -- 12:36 PM EST     2.37 knots Max Flood
Wed -- 03:51 PM EST     -0.01 knots Slack
Wed -- 05:08 PM EST     Sunset
Wed -- 07:24 PM EST     -2.27 knots Max Ebb
Wed -- 08:21 PM EST     Moonrise
Wed -- 11:14 PM EST     0.01 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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22.11.80.9-0.6-1.7-2.1-2.2-2-1.6-0.80.82.22.31.91.1-0.2-1.5-2-2.2-2.2-2.1-1.7-0.4

Weather Map and Satellite Images
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GOES Local Image of Mid-Atlantic    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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Wind Forecast for Philadelphia/Mount Holly, PA (12,3,4,5)
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Ground Weather Radar Station Philadelphia, PA
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Disclaimer:
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.