Wednesday, March29, 2017 L-36.com


Marine Weather and Tides
McClellanville, SC

Version 3.4
What's New / NOTES
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.
3/12/2015 - Added section for Gulf current for users in the GMZ marine zones.
This was requested by a user. If you have requests, please let me know.

Sunrise 7:08AMSunset 7:39PM Wednesday March 29, 2017 5:09 AM EDT (09:09 UTC) Moonrise 7:22AMMoonset 8:31PM Illumination 4% Phase: Waxing Crescent; Moon at 2 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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AMZ350 Waters From South Santee River To Edisto Beach Sc Out 20 Nm- 327 Am Edt Wed Mar 29 2017
Today..NW winds 5 to 10 kt...becoming E 10 to 15 kt late. Seas 3 to 4 ft.
Tonight..NE winds 15 kt. Seas 3 to 4 ft.
Thu..E winds 15 kt. Seas 4 to 5 ft. A slight chance of showers in the afternoon.
Thu night..SE winds 15 to 20 kt with gusts to 25 kt. Seas 4 to 5 ft. A slight chance of tstms. A chance of showers.
Fri..S winds 15 to 20 kt with gusts to 25 kt. Seas 4 to 6 ft. Showers with a chance of tstms.
Fri night..SW winds 15 to 20 kt...becoming W 10 to 15 kt after midnight. Seas 4 to 6 ft. A chance of showers and tstms...mainly in the evening.
Sat..W winds 10 to 15 kt. Seas 3 to 4 ft.
Sat night..W winds 5 to 10 kt. Seas 2 ft.
Sun..NE winds 5 to 10 kt. Seas 2 ft.
Sun night..SE winds 5 to 10 kt. Seas 2 ft. Mariners are reminded that winds and seas can be higher in and near tstms.
AMZ300 327 Am Edt Wed Mar 29 2017
Synopsis for the coastal waters of south coastal south carolina and north coastal georgia.. A weak front will sag south over the area today...then move north as a warm front Thursday night. A cold front will move through Friday night followed by dry high pressure into Sunday. Unsettled weather should return again next Monday, possibly lasting into Tuesday.

7 Day Forecast for Marine Location Near McClellanville, SC
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location: 33, -79.36     debug


Area Discussion for - Wilmington, NC
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Fxus62 kilm 290526
afdilm
area forecast discussion
national weather service wilmington nc
126 am edt Wed mar 29 2017

Synopsis
A cold front which will drop south across the area by late
tonight or early wed. Relatively cooler and drier high pressure
will build in from the north Wed into Thu night. Showers and
thunderstorms are expected on Fri as warmer and more humid air
returns ahead of an approaching cold front. The cold front will
sweep eastward across the area and offshore late Fri night. Some
of the thunderstorms may become strong to severe fri. The
weekend should be dry and warm on Sat with temps dropping back
to near normal on Sun as high pressure builds in from the great
lakes.

Near term /through today/
As of 945 pm Tuesday... Sfc cold front will sink slowly across
the area overnight. The convergence along this front is evident
with CU and sc strewn along it from west to east. A few of these
cu are building just enough to produce isolated showers.

However, aloft, NVA ie. Subsidence, is now affecting the fa with
the mid-level s/w trof having pushed off the DELMARVA coast
this evening. As a result, do not expect much vertical
development with these showers. May continue the slight chance
pop well into this evening as this boundary drops southward.

Not much tweaking to tonights lows from the previous fcst
update. However, am concerned for the possibility of fog
eventhough models are not highlighting its potential. Will
update to include patchy for now and could get worse with time
depending how much drier air, ie. Lower dewpoints, are able to
advect into the fa overnight. Seen it many times after FROPA in
the evening and winds go NW to N less than 5 kt. And with ground
moisture avbl from rainfall having occurred earlier today and
also late this aftn and evening.

Previous... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ..

As of 3 pm Tuesday... A second shortwave is crossing the
carolinas this afternoon and with the early shortwave there has
been a delay in additional convection developing. The goes-16
1-minute imagery is showing cumulus developing west of florence
to pembroke and isolated cumulus developing to the west. The 16
utc hrrr is only showing isolated convection through sunset. So
will keep a 20 to 30% chance of convection with the higher
chances for the northern coastal areas.

The frontal boundary will shift across the area after midnight and
sweep to the south with high pressure building in the area into
Wednesday. Lows tonight are expected to fall into the upper 50s and
highs on Wednesday to around 80 except cooler at the beaches with a
northeast flow.

Short term /tonight through Thursday night/
As of 3 pm Tuesday... Mid level ridge axis over the southeast will be
deamplifying and shifting east Wed night as surface high over
southern canada builds down the east coast. Cooler air associated
with the canadian high spreads over the region Wed night with lows
dropping close to climo. Northeast winds will be in the 5 to 8 mph
range which should prevent any radiational cooling. Low will be in
the low to mid 50s across much of the area. Surface high shifts off
the coast later Thu with weak return flow developing Thu night.

Ridging aloft Wed night and Thu will keep the region dry through at
least Thu evening. Forecast soundings show impressive subsidence
from 850mb through 700mb into Thu night before approaching high
amplitude southern stream system shunts the 5h ridge axis
farther off the coast.

Developing deep southwest flow Thu night increases moisture in
the region, precipitable water values increase from around 0.80"
thu evening to 1.40" by the end of the period. Arrival of this
deeper moisture along with an increase in mid level lapse rates
should open the door for some convection late in the period. The
unfavorable timing and lack of strong low level jetting does
suggest coverage will be rather limited and do not plan on much
in the way of changes to inherited Thu night precip chances.

Temperatures Thu will be near to slightly below climo, upper 60s
to lower 70s, with temps Thu night running above to well above
climo and likely following an atypical curve with slight warming
after midnight.

Long term /Friday through Tuesday/
As of 300 am Tuesday... Next in series of potent southern stream
systems will impact the eastern carolinas Fri and Fri night with
a categorical risk for showers and thunderstorms developing.

The combination of significant upper level support and strong
and deep moisture return and lift provides at least the
opportunity for a more widespread and significant rainfall
event. There will be some risk for strong to severe
thunderstorms during this time. 0-6 km effective bulk shear
parameters are not particularly impressive. However, instability
does grow with mixed layer CAPE values on the order of 500 to
1000 j/kg as the warm front should move to our n. Mid-level
lapse rates are forecast to be rather modest. The potential is
there for an active day/night leading into the weekend, although
magnitude is certainly still a question mark.

In the wake of this system, dry weather and near to above
normal temps are expected for the weekend as mid-level ridging
builds across the area and surface high pressure builds from the
nw and n. Attention then will turn westward as next southern
stream system along the gulf coast Sun night lifts to the NE and
drags a warm front to the n. This will again bring deep
moisture into the carolinas, and with that, showers and
thunderstorms early next week. Given timing differences between
long range models and a general slower trend as compared to 24
hours ago, will cap pops in the chance category until we can
gain better resolution as to when the highest risk for showers
and thunderstorms will occur.

Aviation /06z Wednesday through Sunday/
As of 0530z...VFR conditions expected through the period. Some
fog has developed to the north where there was more rainfall in
the past 24 hours. However the lower dewpoints have begun to
make progress from the northwest with lbt dropping six degrees
in the past hour. Can't rule out a brief period more along the
coast but confidence is not sufficient to include in the
forecast. Some scattered to broken ceilings of four thousand
feet should develop late morning moreso across the northern
areas as a push of cold air noses in from the northeast.

Extended outlook...VFR conditions through Thursday. MVFR/ifr
conditions likely in showers and strong to severe thunderstorms
fri/fri night.VFR conditions Sat thru sun.

Marine
Near term /through Wednesday/...

as of 945 pm Tuesday... Update concerned with pcpn eventually
ending late this evening. And, re-adjusting the winds based on
the slowly southward dropping sfc boundary that will result in
winds becoming NW to N after its passage during this evening
thru the pre-dawn Wed hours. The sfc pg is rather loose on
either side of the sfc cold front, resulting with only 10 to 15
kt wind speeds being fcst. Significant seas will run 2 to 4 ft
with 5 footers across the outer waters off CAPE romain and cape
fear. The healthy SE ground swell at 10 to 11 second periods
has peaked during today and should now exhibit a slow decaying
trend. Will see wind driven waves become more dominant in the
seas spectrum later Wed as NE winds increase due to sfc ridging
down the east coast from canada becoming more prominent.

Previous... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... .

As of 3 pm Tuesday... Sw winds around 15 knots with higher gust
are seen at coastal cman stations... Not receiving any offshore
buoy data at this minute so have lower confidence of the current
wind speeds at 10 to 20 miles off the coast. With cold front
approaching expect to see winds increase to 15 to 20 knots with
higher gust. Seas are expected to peak at 3 to 5 feet. Will
continue to see longer period swells through this evening. With
the cold frontal passage expected between 2 am and 6 am
Wednesday, seas will slowly fall to the 3 to 4 feet range by the
end of Wednesday.

Short term /Wednesday night through Thursday night/...

as of 3 pm Tuesday... Northeast flow will continue Wed night and
thu as high pressure over southern canada builds south.

Gradient becomes pinched late Wed night as cold surge moves
across the waters and northeast flow may briefly hit 20 kt.

Northeast flow remains 15 to 20 kt Thu before starting to
decrease and veer to east Thu evening and then southeast thu
night as the surface ridge axis moves offshore. Seas will range
from 3 to 5 ft through Thu night with shorter wave periods
expected given the strength of the northeast flow. Exercise
caution headlines may be needed during the period, depending on
the strength of the northeast surge late Wed night.

Long term /Friday through Sunday/...

as of 300 am Tuesday... A small craft advisory is likely for all
waters Fri and Fri night with conditions possibly lingering
into sat.

Slow moving area of low pressure will be moving across the ohio
valley fri. Its accompanying warm front will move across the
waters fri. As low pressure moves offshore of the mid-atlantic
states late Fri night and Sat morning, it will strengthen and
drag a cold front across the waters. High pressure will slowly
build across the area from the N and NW Sat night and sun.

Se winds Fri morning will become S and then SW Fri night. The
wind direction will become westerly early Sat morning and then
nw by Sat afternoon. N winds Sat night will become NE overnight
sat with NE winds persisting into Sun before veering to easterly
during the afternoon.

The strongest winds are expected Fri and Fri night, up to 20 to
25 kt. Seas late Fri and Fri night will build to 4 to 7 ft and
around 8 ft at frying pan shoals. Seas during Sat will only slowly
subside as backswell from departing storm system impacts the
waters. Seas should drop below advisory levels by late Sat and
to 2 to 4 ft on sun.

Ilm watches/warnings/advisories
Sc... None.

Nc... None.

Marine... None.

Synopsis... Dch
near term... Dch/drh
short term... Iii
long term... Rjd
aviation... Shk
marine...



Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
NIWS1 - North Inlet-Winyah Bay Reserve, SC 26 mi84 min WNW 5.1 64°F 1014 hPa62°F
CHTS1 34 mi51 min W 5.1 G 7 67°F 64°F1013.6 hPa
FBIS1 - Folly Island, SC 35 mi69 min W 4.1 G 5.1 65°F 1014.2 hPa (-1.0)64°F
41004 - EDISTO - 41 NM Southeast of Charleston, SC 37 mi79 min WSW 16 G 19 69°F 71°F5 ft1013 hPa (-0.8)65°F

Wind History for Charleston, SC
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Georgetown County Airport , SC22 mi14 minN 010.00 miFair57°F55°F94%1014.2 hPa
Mount Pleasant Regional-Faison Field, SC24 mi14 minN 07.00 miFair63°F60°F94%1013.9 hPa

Wind History from GGE (wind in knots)
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Last 24hrCalmSW5SW5SW6SW12
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S12S9S9SW8S5SW6SW6SW5SW4SW5W5CalmCalmNW3
1 day agoCalmCalmCalmCalmSW3S8S7CalmS4S7
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S5S4S5S3CalmCalmCalmCalmS4SW5S6
2 days agoCalmCalmCalmCalmSE3S9SE10SE13S9SE13
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SE10SE5SE5CalmCalmCalmCalmCalmCalmCalmCalm

Tide / Current Tables for Cape Romain, South Carolina
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Cape Romain
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Wed -- 03:23 AM EDT     -0.56 feet Low Tide
Wed -- 07:08 AM EDT     Sunrise
Wed -- 08:21 AM EDT     Moonrise
Wed -- 09:27 AM EDT     5.17 feet High Tide
Wed -- 03:41 PM EDT     -0.63 feet Low Tide
Wed -- 07:35 PM EDT     Sunset
Wed -- 09:30 PM EDT     Moonset
Wed -- 09:47 PM EDT     5.70 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
2.91.40.2-0.5-0.40.623.54.55.15.14.43.21.80.5-0.4-0.60.21.73.34.65.55.75.2

Tide / Current Tables for Five Fathom Creek entrance, South Carolina
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Five Fathom Creek entrance
Click for Map
Wed -- 03:33 AM EDT     -0.60 feet Low Tide
Wed -- 07:09 AM EDT     Sunrise
Wed -- 08:22 AM EDT     Moonrise
Wed -- 09:43 AM EDT     5.41 feet High Tide
Wed -- 03:51 PM EDT     -0.67 feet Low Tide
Wed -- 07:36 PM EDT     Sunset
Wed -- 09:31 PM EDT     Moonset
Wed -- 10:03 PM EDT     5.95 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
3.31.80.4-0.5-0.50.31.83.34.55.25.44.83.72.20.7-0.3-0.7-01.43.14.65.665.6

Weather Map and Satellite Images
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Weather Map
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IR Satellite Image from GEOS
east_satellite

GOES Local Image of Southeast    EDIT
Geos

Wind Forecast for Wilmington, NC (5,6,7,8)
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Ground Weather Radar Station Wilmington, NC
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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.