Marine Weather and Tides
5/20/2018 -- NOAA is having problems with the data feed that I use to draw the graphs. They are aware of the issue and working to resolve it. Sometimes changing the location by about a mile will give a correct graph. 3/3/2018 - There is a new GOES Satellite for the east coast that required rewriting that part of the code. Please report any issues.
|Sunrise 5:35AM||Sunset 8:35PM||Saturday June 23, 2018 2:06 PM EDT (18:06 UTC)||Moonrise 3:23PM||Moonset 1:51AM||Illumination 78%|
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|ANZ530 Chesapeake Bay North Of Pooles Island- 132 Pm Edt Sat Jun 23 2018 |
This afternoon..S winds 5 to 10 kt. Waves 1 ft. Showers likely with a chance of tstms. Vsby 1 nm or less.
Tonight..SW winds 5 to 10 kt. Waves 1 ft or less. A chance of showers and tstms. Vsby 1 nm or less.
Sun..W winds 5 to 10 kt. Waves 1 ft. A chance of showers and tstms.
Sun night..NW winds 5 to 10 kt. Waves 1 ft.
Mon..N winds 5 to 10 kt. Waves 1 ft.
Mon night..N winds 5 to 10 kt. Waves 1 ft.
Tue..S winds 5 to 10 kt. Waves 1 ft or less.
Wed..S winds 10 to 15 kt. Waves 1 to 2 ft. A chance of showers and tstms through the day, then showers and tstms likely through the night. Winds and waves higher and visibilities lower in and near tstms.
|ANZ500 132 Pm Edt Sat Jun 23 2018 |
Synopsis for the tidal potomac and md portion of the chesapeake bay.. A warm front will slowly move northward across the waters today. Meanwhile, low pressure over the ohio valley will move into the eastern great lakes. This low will continue moving eastward across new england Sunday bringing a cold front across the waters. High pressure will return Monday and Tuesday.
7 Day Forecast for Marine Location Near Cecilton, MDHourly EDIT Help
Area Discussion for - Philadelphia/Mount Holly, PA  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus61 kphi 231749|
area forecast discussion
national weather service mount holly nj
149 pm edt Sat jun 23 2018
A low pressure system in the great lakes region leads to a warm
frontal passage in our area today and a cold frontal passage
tomorrow. High pressure over ontario builds into the region on
Monday and slowly moves off the eastern seaboard to a position near
bermuda by Thursday. A trough may move through our region Wednesday
night into Thursday.
Near term until 6 pm this evening
Just sent out another update. Wasn't scheduled, but I wasn't
liking how temps were tracking. Bump the temps grids down again
pretty much north and west of the i95 corridor. Looks like the
coastal plain will see some breaks, so left temps as is there.
looks like the warm front is across southern de at this time.
Kged went south for an hour earlier, but it's back to the
northeast. Ocean city, md is southeast. Northeast winds are
holding firm across much of the region north of the front. There
is some clearing across va working this way.
I made a few adjustments this update... I lowered temps across
se pa and central nj once again. I am below guidance, but may
not be low enough. History suggests I am forecasting 80 for
locales that probably won't get there. A warm front like today
is not a meteorologist's best friend. Sure to take one on the
Adjustments were also made to the winds grids. Kept them more ne.
Not sure this warm front will get north of the pa turnpike or
nj i-195 today.
Adjustments were also made to the pop grids. I scaled back
following the near-term hi-res solutions. SPC still has the our
southern zones in a slight risk, so enhanced wording has been
maintained across this area.
previous discussion outlines today's forecast challenges as well as
the issues this warm front poses. Temps, winds, cloud cover and fog,
precip and a severe threat. These are all in play. What's standing
out this morning is the northeast winds across the region. The mav
stat guidance is more easterly, the met guidance is better as are
the near-term hi-res models. The question in my head this morning
is, is this warm front going to have more issues moving north today?
soundings suggest southwest winds in the 5-15k foot range around 15
to 30 kt, not necessary the speeds one wants to see to accelerate a
front northward. Grant it, the ocean has warmed considerably, and
this isn't march, so the cool low-level pool on the north side of
the front isn't all that cool. The front is draped across the
southern DELMARVA zones at this time. Wpc has it moving north to pa
turnpike i-195 in nj by 18z and up to near i80 by 00z. This
progression simply might be too fast with this NE flow. That said, i
shaved off a degree or two across mid-zones in SE pa and central nj.
Confidence remains low.
The other thing to mention this morning is the vast difference in
pops comparing low-resolution and stat guidance vs. Near-term hi-res
models. The latter has a lot less coverage. Our current trends still
fit as we are highlighting pa and northern nj with the best precip
chances today. I wouldn't be surprised if locations from southern
ocean county southward into the de and out md zones see very little
until this evening. Although this area may not see a widespread
shower thunder activity today, with the proximity of the front, low
clouds and fog will be prevalent making for a dreary day, at least
through this morning. We'll check back midday and amend were
through 10 am...
mid-level shortwave energy and the lf quadrant of the upper jet,
aided by orographic lift in the easterly low-level flow, within a
very moist airmass (pw values ~ 2 inches) will lead to heavy showers
across the lehigh valley and southern poconos. Further southeast, a
wave of low pressure developing along the warm front just to the
south will lead to enhanced isentropic ascent across portions of
southern nj and delaware, where heavy showers are also possible.
Cannot rule out a rumble of thunder, with the greatest probability
over far southern nj and delmarva. In addition, some of the heaviest
rain showers could lead to localized rainfall amounts up to 1" hour
but fast movement should preclude more than poor drainage flooding.
10 am thru 6 pm...
the warm front will begin to make northward progress, but there is
still uncertainty regarding its position by late afternoon. The gfs
and ECMWF are in better agreement with the NAM for the 00z 23 model
suite, and have the front located INVOF i-276 in pa northeastward to
i-95 in nj by late afternoon. Any deviation in this position north
or south will have a profound impact on severe weather potential and
high temp forecast.
Severe weather potential...
spc has outlooked a slight risk for extreme southeast pa and
southern nj, with a marginal risk from portions of the lehigh valley
to include all of ocean county nj.
Across the slight risk area, favorable parameters continue, with ml
cape ~1,500 j kg and bulk shear around 45 kt. Gusty winds are
possible, although modest 0-3 km lapse rates and meager d-cape
suggest damaging winds will be limited in coverage. Still very
concerning is the environment closer to the warm front, where 0-1 km
shear over 20 kts and low lcls could favor a brief, weak tornado.
Hail parameters, including lapse rates in the hail growth zone,
remain weak so would expect mainly small hail. The exception would
be any rotating updrafts closer to the warm front, which would be
more favorable for large hail.
With precipitable water values ~2 inches, heavy downpours are
likely, especially if thunderstorms train near the warm front,
which may result in urban and poor drainage flooding.
a warm and humid airmass will advect northward to the aforementioned
area. South of the front, southerly flow, partly cloudy skies, and
mixing up to 850 hpa support highs in the mid to upper 80s. North of
the front, considerable cloudiness and an easterly flow will keep
temps in the 70s. Any oscillation in the frontal position could
raise lower temperatures 10-15 degrees at a given location.
Short term 6 pm this evening through 6 am Sunday
The severe weather threat should diminish around 03z with the loss
of instability and shear. The shortwave axis and pre-frontal trough
also move offshore around midnight, with subsidence taking hold
through column and dryer air advecting in. There may be some partial
clearing, and with the moist ground, this would be conducive for the
development of fog. But near surface winds out of the west are
expected to remain elevated much of the night, so confined patchy
fog to the more sheltered locations of northern nj and southeast pa.
Low temperatures are expected to be a few degrees above normal.
Long term Sunday through Friday
Summary: thunderstorms are possible on Sunday as a cold front|
arrives in the region. High pressure will bring tranquil weather
Monday and Tuesday. Chances for showers and thunderstorms again
increase Wednesday through Thursday as a trough approaches from
Sunday... In the mid and upper levels, winds become more westerly
early in the day on Sunday resulting in dry air advection. A mid
and upper level trough digging southeast will arrive just behind
the surface cold front late in the day. Despite still being in
the warm sector that will be responsible for thunderstorms
today, the dry air advection and a mid level inversion should
limit instability on Sunday. Thunderstorms are possible, but
strong or severe thunderstorms are not expected at this time.
Monday and Tuesday... Canadian high pressure builds south. The
cold front will only drop temperatures to near normal. Forecast
temperatures, especially on Tuesday are higher than most
guidance as the pattern favors very large dew point depressions
in the boundary layer. Models typically underestimate the depth
of the mixing layer in these cases which could result in higher
than forecast MAX temperatures and lower than forecast dew
Wednesday and Thursday... Another large low pressure system,
taking a track further north than the one today, will bring a
trough into the region either Wednesday night or Thursday. Ahead
of this trough, southerly low level return flow develops,
resulting in moisture and warm air advection. There are still
some timing differences between the models on the trough, which
has an impact both on rain chances and temperatures. Have gone
with a middle of the road solution, bringing the trough through
late Wednesday night Thursday morning, resulting in modest
warming trend on Wednesday, but significantly warmer on
Thursday. In this scenario, the prime period for showers and
thunderstorms across our region would be Wednesday night and
Thursday, though some may develop primarily west of the fall
line on Wednesday afternoon thanks to enhanced orographic lift.
Friday... A high should start building in from the southwest. How
quickly it does so will determine if we see another round of
showers and thunderstorms during the day Friday and how quickly
really muggy conditions return to the area. Given the source
region of this air mass, would not be surprised if heat index
values once again get above 100, if not on Friday, then likely
Aviation 18z Saturday through Thursday
The following discussion is for kphl, kpne, kttn, kabe, krdg,
kilg, kmiv, kacy and surrounding areas.
widespread ifr CIGS this morning will gradually improve late this
morning withVFR at most locations by late afternoon. The exception
will be abe and rdg, where CIGS will only improve to mfvr. Medium
Winds easterly this morning, gradually shifting to south-southwest
late this morning into the afternoon, except abe and rdg where winds
remain easterly. South-southwest winds could gust up to 25 mph. Low
During the afternoon into the evening, shra and tsra are expected at
most terminals, accompanied by brief cig vsby restrictions and gusty
winds. High confidence.
Saturday night... Tsra possible until around 03z. Thereafter, MVFR in
low clouds and patchy fog, mainly abe, rdg, miv, and acy. West winds
less than 10 kt. Low confidence.
Sunday... MVFR conditions will be possible with any showers and
thunderstorms that develop. Otherwise,VFR conditions are
expected. Winds will be shifting to northwesterly behind a cold
front, but wind speeds should remain near or below 10 kt.
Monday and Tuesday...VFR conditions are expected. Northwesterly
winds on Monday become light and variable Monday night into
Tuesday. High confidence.
Wednesday... MostlyVFR conditions are expected. There is a
chance for showers and thunderstorms to move in through the day,
especially at kabe and krdg. If this happens, MVFR conditions
will be possible. Moderate confidence.
Made more adjustments to the winds with the warm front having
issues pushing north.
updated the winds. They're more from the NE this morning.
Confidence is low with the winds today. Shifting from the south
depends on how far north this warm front gets.
sca continues for the atlantic de nj and lower de bay waters
through this evening. East-southeast winds this morning 15-20
kt, shifting to south-southwest this afternoon 10-20 kt,
becoming west-southwest around 10 kt tonight. Gusts around 25 kt
are possible today. Seas remaining elevated around 5 ft today
and tonight. Higher winds and seas possible near thunderstorms
this afternoon and evening.
Sunday through Tuesday... Winds and seas should stay below sca
criteria. Thunderstorms are possible on Sunday, but then high
pressure builds in leading to dry conditions.
Wednesday... SCA conditions, for both winds and seas, are
possible. Southerly winds increase ahead of the next low
pressure system. Seas should subsequently increase as well.
easterly winds this morning into the early afternoon shifting to the
south-southwest. Winds may gust up to 25 mph at times. Seas in the
surf zone 3 to 4 ft. A low risk for the formation of dangerous today
for the de beaches. With more of an onshore component of flow and
swell, there is a moderate risk for the nj beaches.
Phi watches warnings advisories
Marine... Small craft advisory until 9 pm edt this evening for
near term... Kruzdlo lf
short term... Lf
long term... Johnson
aviation... Johnson lf
marine... Johnson kruzdlo lf
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|
|DRSD1 - Delaware Reserve, DE||34 mi||156 min||ENE 1.9||70°F||1011 hPa||70°F|
|44063 - Annapolis||45 mi||36 min||NNE 1.9 G 1.9||72°F||1010.2 hPa|
|TPLM2 - Thomas Point, MD||49 mi||66 min||N 1.9 G 2.9||72°F||74°F||1011 hPa (+0.0)||71°F|
Wind History for Chesapeake City, MD(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Wilmington, New Castle County Airport, DE||21 mi||75 min||E 6||8.00 mi||Overcast||69°F||66°F||90%||1010.8 hPa|
Wind History from APG (wind in knots)
|1 day ago||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||W||NW||Calm||Calm||N||NE||NE||NE||Calm||NE||NE||Calm||Calm||Calm|
|2 days ago||NE||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||NE||NE||NE||E||Calm||Calm||E||Calm||SW||W||W||Calm||Calm|
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Old Town Point Wharf |
Click for Map
Sat -- 12:29 AM EDT 0.59 feet Low Tide
Sat -- 02:51 AM EDT Moonset
Sat -- 05:37 AM EDT Sunrise
Sat -- 07:16 AM EDT 3.38 feet High Tide
Sat -- 02:00 PM EDT 1.07 feet Low Tide
Sat -- 04:22 PM EDT Moonrise
Sat -- 07:08 PM EDT 2.37 feet High Tide
Sat -- 08:34 PM EDT Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Chesapeake and Delaware Canal |
Click for Map
Sat -- 01:38 AM EDT 0.01 knots Slack
Sat -- 02:50 AM EDT Moonset
Sat -- 04:09 AM EDT 2.07 knots Max Flood
Sat -- 05:36 AM EDT Sunrise
Sat -- 07:47 AM EDT -0.01 knots Slack
Sat -- 10:04 AM EDT -1.51 knots Max Ebb
Sat -- 01:20 PM EDT 0.01 knots Slack
Sat -- 04:11 PM EDT 2.03 knots Max Flood
Sat -- 04:22 PM EDT Moonrise
Sat -- 07:01 PM EDT -0.05 knots Slack
Sat -- 08:34 PM EDT Sunset
Sat -- 10:27 PM EDT -2.23 knots Max Ebb
Tide / Current data from XTide NOT FOR NAVIGATION
Weather Map and Satellite Images(on/off)  HelpWeather Map
GOES Local Image of EDIT
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Wind Forecast for Philadelphia/Mount Holly, PA (14,3,4,5)(on/off)  Help
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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.