Marine Weather and Tides
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 6:43AM||Sunset 5:51PM||Saturday February 23, 2019 10:51 AM EST (15:51 UTC)||Moonrise 10:44PM||Moonset 9:26AM||Illumination 82%|
7 Day Forecast for Marine Location Near Cambridge, MDHourly EDIT Help
Area Discussion for - Philadelphia/Mount Holly, PA  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus61 kphi 231423|
area forecast discussion
national weather service mount holly nj
923 am est Sat feb 23 2019
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
Adjusted temps just a bit to match current observations and
trends. The ten degree difference between air temperature and
dewpoint temperature on the DELMARVA will need to decrease
several degrees before precipitation can begin south of the c&d
canal. Forecast remains 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
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
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
Moderate to locally heavy rain continue through Sunday morning,
tapering off from southwest to northeast as that secondary low
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
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 14z Saturday through Wednesday
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
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.
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.
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.
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
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.
The majority of the rain will fall this evening through midday
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
Nj... High wind watch from Sunday evening through Monday afternoon
De... High wind watch from Sunday evening through Monday afternoon
Md... High wind watch from Sunday evening through Monday afternoon
Marine... Gale watch from Sunday evening through Monday afternoon for
Small craft advisory from 6 am to 6 pm est Sunday for anz430-
Storm watch from Sunday evening through Monday afternoon for
near term... Miketta mps
short term... Mps
long term... Staarmann
aviation... Cms mps staarmann
marine... Miketta mps staarmann
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|
|CA2 - 8571892 - Cambridge, MD||1 mi||51 min||39°F||41°F||1031.1 hPa (+0.0)|
|COVM2 - 8577018 - Cove Point LNG Pier, MD||20 mi||51 min||E 4.1 G 5.1||39°F||1031.5 hPa (+0.0)|
|BISM2 - 8571421 - Bishops Head, MD||24 mi||51 min||E 6 G 8.9||41°F||42°F||1030.9 hPa (+0.0)|
|SLIM2 - 8577330 - Solomons Island, MD||26 mi||51 min||ENE 5.1 G 6||40°F||40°F||1030.6 hPa (+0.0)|
|TPLM2 - Thomas Point, MD||30 mi||51 min||ENE 7 G 8||37°F||38°F||1031.9 hPa (-0.3)||28°F|
|CPVM2||34 mi||51 min||38°F||28°F|
|APAM2 - 8575512 - Annapolis, MD||36 mi||51 min||38°F||1030.8 hPa (+0.0)|
|BSLM2 - Chesapeake Bay, MD||36 mi||141 min||ENE 2.9||38°F||1032 hPa||29°F|
|44042 - Potomac, MD||39 mi||39 min||E 7.8 G 7.8||39°F||40°F||1031.2 hPa|
|PPTM2 - 8578240 - Piney Point, MD||39 mi||57 min||ESE 8 G 8|
|LWTV2 - 8635750 - Lewisetta, VA||45 mi||51 min||E 6 G 7||41°F||41°F||1030.5 hPa (+0.0)|
|TCBM2 - 8573364 - Tolchester Beach, MD||45 mi||51 min||ENE 4.1 G 5.1||37°F||40°F||1031.6 hPa (+0.0)|
|DRSD1 - Delaware Reserve, DE||49 mi||141 min||NE 2.9||37°F||1032 hPa||30°F|
Wind History for Cambridge, MD(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Cambridge-Dorchester Airport, MD||3 mi||71 min||Var 5||9.00 mi||Fair||39°F||32°F||75%||1031.2 hPa|
|Easton / Newman Field, MD||16 mi||62 min||ENE 6||10.00 mi||Clear||39°F||30°F||70%||1032.2 hPa|
Wind History from CGE (wind in knots)
|1 day ago||SW||N||N||NW||NW||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||NW||N||NW||Calm||Calm||N||N||N|
|2 days ago||E||N||E||E||E||Calm||Calm||N||Calm||NW||NW||Calm||NW||NW||NW||NW||W||SW||Calm||Calm||SW||Calm||S |
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Wind Forecast for Philadelphia/Mount Holly, PA (10,2,3,4)(on/off)  Help
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