Saturday, February23, 2019 L-36.com


Marine Weather and Tides
Atglen, 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 6:44AMSunset 5:49PM Saturday February 23, 2019 3:38 PM EST (20:38 UTC) Moonrise 10:45PMMoonset 9:25AM Illumination 80% Phase: Waning Gibbous; Moon at 19 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
    EDIT      (on/off)   Help
ANZ530 Chesapeake Bay North Of Pooles Island- 1240 Pm Est Sat Feb 23 2019
This afternoon..SE winds 5 kt. Waves less than 1 ft. Rain.
Tonight..SE winds 5 kt. Waves less than 1 ft. Rain. Vsby 1 to 3 nm.
Sun..SW winds 10 to 15 kt with gusts to 25 kt... Becoming W 20 to 25 kt with gusts to 40 kt late. Waves 1 ft...building to 3 ft in the afternoon. Showers.
Sun night..W winds 20 to 25 kt. Gusts up to 40 kt... Diminishing to 30 kt after midnight. Waves 3 ft.
Mon..W winds 15 to 20 kt with gusts to 40 kt. Waves 3 ft.
Mon night..NW winds 10 to 15 kt. Gusts up to 25 kt in the evening. Waves 1 to 2 ft.
Tue..N winds 5 to 10 kt. Waves 1 ft.
Wed..NW winds 5 kt. Waves less than 1 ft. A chance of snow showers through the night.
ANZ500 1240 Pm Est Sat Feb 23 2019
Synopsis for the tidal potomac and md portion of the chesapeake bay.. Low pressure will approach the middle mississippi river valley tonight, strengthening as it moves northeastward across the great lakes into canada through Sunday. High pressure will build from the northern great plains toward the great lakes and eventually into the northeast through the first half of next week. Gale conditions are likely over the waters Sunday into Monday.


7 Day Forecast for Marine Location Near Atglen , PA
   Hourly   EDIT   Help
location: 39.9, -76     debug


Area Discussion for - Philadelphia/Mount Holly, PA
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus61 kphi 231739
afdphi
area forecast discussion
national weather service mount holly nj
1239 pm est Sat feb 23 2019

Synopsis
High pressure centered across the region will push offshore
today. An expansive area of strong low pressure will strengthen
and move from the southern plains and cross the great lakes
through Sunday pushing a cold front across our area late Sunday
afternoon. High pressure will build through late Tuesday behind
this storm system yielding fair weather for the beginning of
the week. A weak low pressure system may affect the region
Wednesday, then high pressure returns through the end of the
week. More unsettled weather is possible next weekend.

Near term until 6 pm this evening
Temperatures are running just a bit cooler than previously
expected, so high temps were tapped down just a bit for the
early afternoon update. Rain is starting to move north into the
far southern portions of the cwa, and a slow progression
northward is still expected. Pops have been adjusted just a bit
to match current observations. Rest of forecast is still on
track.

Otherwise, 1035 mb high pressure centered over new york state
will slowly move into northern new england later this morning,
then south and east of CAPE cod this afternoon. Meanwhile, low
pressure continues to develop and organize over the plains
states, and will lift through the midwest later today.

Overrunning precip will develop out ahead of that low and lift
towards the mid-atlantic later this afternoon. What remains to
be seen is how much northeast progression the precip shield will
make today due to the strength of the offshore high. 12z nam
has precip getting into DELMARVA late in the day, so will follow
the trend of slowing the precip down. Will have likely pops
through DELMARVA this afternoon, but categorical pops will hold
off until this evening. No ptype issues in delmarva, as temps
will be quite warm today.

Highs today will top off in the upper 30s in the southern
poconos to the low 40s north and west of the fall line.

Otherwise, highs today top off in the mid to upper 40s.

Short term 6 pm this evening through 6 pm Sunday
High pressure moves out to sea this evening. Low pressure over the
midwest continues to track to the north and east, and should be over
the upper great lakes by daybreak Sunday. Meanwhile, some shortwave
energy spinning out ahead of that low will move into the mid-
atlantic, and a secondary low forms just south of DELMARVA late
tonight. This low then lifts through new jersey and then south and
east of long island on Sunday.

A warm front extending out ahead of the primary low will lift
through the mid-atlantic and towards the northeast late tonight as
that secondary low is forming. Overrunning precip lifts to the north
and east this evening, but the steadier and more widespread precip
will not arrive until that secondary low forms and lifts through the
region. Based on latest model analysis, the timing of the heavier
precip looks to hold off until after midnight, and may not affect
the bulk of the forecast area until the pre-dawn hours Sunday and
through Sunday morning.

Hourly pop grids will show a slow southwest to northeast track in
the likely categorical precip, but overall, categorical pops
expected tonight.

One thing of concern - the southern poconos and far northern new
jersey (generally sussex county). Temps look to drop to just below
freezing, generally 29-31 degrees. As that overrunning precip lifts
to the north, there may be a brief period of some freezing rain
before the heavier precip allows the warmer air to mix down and
change precip to plain rain. For now, will mention a chance of
freezing rain, and if this occurs, it would be for a couple of hours
in the late evening. Confidence is way to low to justify a winter
weather advisory for this, but will mention the possibility in the
hwo.

Highest pwats across the region will be around 1.5", generally
across DELMARVA and southern nj, in the vicinity of the formation of
the secondary low. Between 1.25-1.5" of rain is expected to fall in
these areas tonight through Sunday morning. Although poor drainage
flooding is possible, not anticipating widespread flooding that
would necessitate a flood watch at this time. Elsewhere, generally
0.50-1.00".

Moderate to locally heavy rain continue through Sunday morning,
tapering off from southwest to northeast as that secondary low
departs.

Primary low lifts north of the great lakes and towards eastern
canada, several strong shortwaves will rotate around the low and
into the ohio valley and northeast during the day Sunday, probably
keeping at least scattered showers in the forecast through the
afternoon.

Primary low also intensifies from a 979 mb low over the great lakes
Sunday morning to a 970 mb low north of the great lakes by Sunday
evening. A tight pressure gradient will form between that low, high
pressure over the western atlantic, and another area of high
pressure building from western canada and nosing its way down into
the northern plains states. In addition, a 50-60 kt LLJ will move
into far western zones, and this tracks east in the late
afternoon early evening hours. Think mixing will be good for the
western third of the forecast area, generally the southern poconos,
lehigh valley, and the delaware valley, as these winds should arrive
during the last of the daylight hours. Will carry a forecast of 35-
45 mph wind gusts for those areas, and a wind advisory may be needed
for at least these areas late Sunday.

Long term Sunday night through Friday
The main story at this point in time is the strong gradient wind
potential Sunday night through the day Monday. A very strong area of
low pressure will cross the great lakes Saturday night through
Sunday. Guidance indicates this low will bottom out with a pressure
of 965-970 mb Sunday night into Monday over the canadian maritimes
as a strong 1040 mb high pressure spills from southern canada into
the northern plains and midwest. This places our area in a tight
pressure gradient as the system pushes a cold front across the
region late Sunday afternoon. Winds will be very strong (50-60 kts)
just above the surface (850-925 mb) behind this front with modest
cold air advection underway. Just after the front passes, there will
be a sharp pressure rise which will add to the mixing of winds to
the surface late Sunday afternoon and into the evening, so there may
be a period of strong gusty winds during this time. Would not be
surprised to see a few gusts nearing 50 mph just behind the front.

From this point, the evolution of the boundary layer, and its
ability to remain coupled to the surface layer, will determine just
how much strong wind reaches the surface overnight. The boundary
layer will be well mixed, particularly during the day Monday, but
bufkit data indicates many areas will decouple through the overnight
hours. Fortunately, the strongest winds just above the surface
appear to be in place during this overnight period, when mixing will
not be as efficient. The strongest near surface winds appear to
weaken a few hours after daybreak Monday.

With that said, current thinking is that gusty winds will diminish to
some degree (20-25 sustained with 30-40 mph gusts) during the
overnight hours then ramp up very quickly around sunrise Monday
morning (sustained 25-30 mph with gusts exceeding 55 mph in some
locations, especially north). Wind gusts are likely to be strongest
during the morning hours before slowly slacking off into the
afternoon hours with winds possibly still gusting up to 50 mph.

Winds will diminish into the evening and overnight Monday. Guidance
is in quite good agreement that we will see at least solid wind
advisory criteria area wide. With the potential for a sizable
portion of our area (mainly pa and central northern nj) nearing high
wind warning criteria, will go ahead and issue a high wind watch
given the potentially higher impacts of this event.

Beyond Monday night, things dry out and high pressure settles into
the region. Monday and Tuesday will be dry, mostly sunny, and chilly
with temps below normal. Forecast confidence is low from Wednesday
and beyond. A weak system may bring a few rain and or snow showers
to our area during the day Wednesday, but guidance varies
significantly with the system (or lack thereof). ECMWF is much colder
and drier than the GFS canadian. A weak cold frontal passage is
possible in the wake of this system late Wednesday. Beyond
Wednesday, more high pressure settles into the region Thursday and
fair weather with near normal temps will prevail then clouds and
precip chances will increase into Friday.

Aviation 18z Saturday through Thursday
The following discussion is for kphl, kpne, kttn, kabe, krdg,
kilg, kmiv, kacy and surrounding areas.

Today...VFR. CIGS lowering to around 5000 feet by 00z. Rain should
hold off until after 00z. Lgt vrb winds, becoming SE 5-10 kt this
afternoon
tonight... Ifr lifr conditions in moderate to heavy rain and fog.

Lgt vrb winds.

Sunday... Ifr lifr conditions in moderate to heavy rain and fog in
the morning, gradually becomingVFR late. South winds 5-10 kt,
becoming west 15-20 kt with 25-30 kt gusts in the afternoon.

Outlook...

Sunday night...VFR. Windy with winds 15-20 kts gusting up to 40 kts
from the west. Moderate confidence on winds.

Monday...VFR. Very windy with W NW winds sustained 20-25 kts gusting
40-50 kts. Wind gusts will be stronger during the morning hours.

Moderate confidence on winds.

Monday night...VFR. Winds NW diminishing to around 10 kts overnight.

High confidence.

Tuesday...VFR. With winds NW 5-10 kts.

Wednesday... MainlyVFR, but possibly reduced CIGS vsby in scattered
rain snow showers. Low confidence.

Thursday...VFR. Light northerly winds.

Marine
Sub-small craft advisory conditions today and tonight. Vsby
restrictions in moderate to heavy rain and fog developing tonight
and continuing through Sunday. SCA conditions develop on Sunday on
all waters.

Outlook...

Sunday night... Gale force wind gusts likely developing with storm
force wind gusts possible toward the north later into the overnight.

Monday... Gale force winds likely. Storm force winds possible toward
the north, especially in the morning hours.

Monday night... Gales likely.

Tuesday and Wednesday... Winds and seas diminish below SCA Tuesday
and remain below SCA into Wednesday.

Thursday... Sub-sca expected.

Hydrology
The majority of the rain will fall this evening through midday
Sunday.

Using the 1.00 to 1.50 of qpf, there are responses at our forecast
points. No flooding is currently forecast, but models do put some
crests near bankful. Over the weekend, keep an eye these forecast
points... The north branch rancocas at pemberton, the millstone river
at blackwells mills, the passaic river at millington and pine brook,
and the rockaway river at boonton. Outside of the passaic river,
flooding potential is low on our other mainstem rivers.

So as the event unfolds tonight, look for minor flooding across
areas of poor drainage and in low-lying areas. Some smaller creeks
that have been prone to high water the last six months will be prone
once again this weekend. This water will runoff make it into the
above mentioned larger creeks and streams on Saturday night. Rises
can be expected late tonight, Sunday, Sunday night, and maybe into
Monday. If flooding occurs at any of our forecast points, it appears
the flooding wouldn't initiate until Sunday night.

Phi watches warnings advisories
Pa... High wind watch from Sunday evening through Monday afternoon
for paz054-055-060>062-070-071-101>106.

Nj... High wind watch from Sunday evening through Monday afternoon
for njz001-007>010-012>027.

De... High wind watch from Sunday evening through Monday afternoon
for dez001>004.

Md... High wind watch from Sunday evening through Monday afternoon
for mdz008-012-015-019-020.

Marine... Gale watch from Sunday evening through Monday afternoon for
anz430-431-452>455.

Small craft advisory from 6 am to 6 pm est Sunday for anz430-
431-450>455.

Storm watch from Sunday evening through Monday afternoon for
anz450-451.

Synopsis... Staarmann
near term... Miketta mps
short term... Mps
long term... Staarmann
aviation... Cms mps staarmann
marine... Miketta mps staarmann
hydrology...



Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map
Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
CHCM2 - 8573927 - Chesapeake City, MD 28 mi45 min E 5.1 G 8 40°F 39°F1028.3 hPa
DELD1 - 8551762 - Delaware City, DE 31 mi45 min N 2.9 G 4.1 39°F 35°F1028.1 hPa
MRCP1 - 8540433 - Marcus Hook, PA 32 mi45 min 40°F 40°F1027.9 hPa
RDYD1 - 8551910 - Reedy Point, DE 33 mi45 min 1027.5 hPa
PHBP1 - 8545240 - Philadelphia, PA 46 mi45 min 42°F 39°F1028.2 hPa
BDSP1 49 mi45 min 41°F 41°F1028.7 hPa
TCBM2 - 8573364 - Tolchester Beach, MD 49 mi45 min ENE 4.1 G 6 40°F 39°F1027.7 hPa

Wind History for Chesapeake City, MD
(wind in knots)    EDIT      (on/off)   Help
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
Last
24hr
NW5
G8
N3
NW2
--
--
S1
NW2
W1
--
N1
NE1
NE2
NE4
E4
NE6
E7
G10
NE4
E7
G11
SE4
G8
E4
SE5
SE4
SE5
G8
E4
G7
1 day
ago
W4
G7
W5
W2
NW4
NW4
W3
G6
NW4
NW3
--
NW3
N1
NW4
N2
G5
N4
G7
N3
N3
NW2
N4
N3
G6
N4
NW4
G9
NW6
NW4
N6
2 days
ago
NE6
NE2
G5
E4
E4
N1
E5
E5
G8
NE3
N4
--
W3
W3
W2
G5
SW2
W2
W2
SW1
G4
W3
G6
W4
G7
W2
G6
NW4
NW4
W4
NW5
G9

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Chester County Airport, PA9 mi44 minVar 510.00 miPartly Cloudy37°F28°F70%1027.8 hPa
Lancaster, Lancaster Airport, PA22 mi46 minESE 510.00 miOvercast40°F30°F68%1027.7 hPa

Wind History from MQS (wind in knots)
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
Last 24hr54NW8NW5NW5NW6NW6NW4CalmCalmCalmCalmCalmE4CalmCalmNE4
G10
CalmNE3
G11
NE3E9NE3
G13
64
1 day agoNW11
G16
NW10W11
G17
W9W5W4NW3W4NW9NW9
G14
W7NW8NW8NW12NW8NW9NW5N4N8N5N5N8
G13
NW9N7
2 days agoE96E5
G10
E9E7SE6E7E6NE4E8E7N3CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmW5W7

Tide / Current Tables for Port Deposit, Susquehanna River, Maryland
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Port Deposit
Click for Map
Sat -- 01:11 AM EST     2.23 feet High Tide
Sat -- 06:46 AM EST     Sunrise
Sat -- 08:36 AM EST     -0.40 feet Low Tide
Sat -- 09:25 AM EST     Moonset
Sat -- 01:31 PM EST     2.23 feet High Tide
Sat -- 05:49 PM EST     Sunset
Sat -- 09:09 PM EST     -0.38 feet Low Tide
Sat -- 10:45 PM EST     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

12
am
1
am
2
am
3
am
4
am
5
am
6
am
7
am
8
am
9
am
10
am
11
am
12
pm
1
pm
2
pm
3
pm
4
pm
5
pm
6
pm
7
pm
8
pm
9
pm
10
pm
11
pm
1.92.22.11.81.30.80.3-0.1-0.4-0.40.10.81.62.22.221.510.50.1-0.2-0.4-0.20.3

Tide / Current Tables for Charlestown, Northeast River, Maryland (2)
   EDIT      (on/off)   Help   One Week of Data
Charlestown
Click for Map
Sat -- 12:49 AM EST     2.01 feet High Tide
Sat -- 06:45 AM EST     Sunrise
Sat -- 07:36 AM EST     -0.35 feet Low Tide
Sat -- 09:24 AM EST     Moonset
Sat -- 01:09 PM EST     2.01 feet High Tide
Sat -- 05:49 PM EST     Sunset
Sat -- 08:09 PM EST     -0.34 feet Low Tide
Sat -- 10:44 PM EST     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

12
am
1
am
2
am
3
am
4
am
5
am
6
am
7
am
8
am
9
am
10
am
11
am
12
pm
1
pm
2
pm
3
pm
4
pm
5
pm
6
pm
7
pm
8
pm
9
pm
10
pm
11
pm
1.921.81.40.90.4-0-0.3-0.3-00.51.21.821.91.61.10.60.1-0.2-0.3-0.20.20.8

Weather Map and Satellite Images
       (on/off)   HelpWeather Map
wmap_A
GOES Local Image of    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.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for Philadelphia/Mount Holly, PA (15,3,4,5)
      (on/off)   Help

Ground Weather Radar Station Philadelphia, PA
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

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.