Marine Weather and Tides
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
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.
|Sunrise 6:30AM||Sunset 8:22PM||Friday July 28, 2017 9:03 AM EDT (13:03 UTC)||Moonrise 10:52AM||Moonset 11:00PM||Illumination 24%|
EDIT (on/off)  Help
|AMZ330 Charleston Harbor- 616 Am Edt Fri Jul 28 2017 |
Today..SW winds 5 to 10 kt. A slight chance of showers and tstms.
Tonight..SW winds 10 to 15 kt. A slight chance of showers and tstms in the evening, then a chance of showers and tstms after midnight.
Sat..SW winds 10 to 15 kt. Showers and tstms likely. Locally heavy rainfall possible in the afternoon with vsbys less than 1 nm.
Sat night..W winds 5 to 10 kt, becoming N after midnight. Showers and tstms likely. Locally heavy rainfall possible in the evening with vsbys less than 1 nm
Sun..NE winds 10 kt. A chance of showers and tstms in the morning.
Sun night..NE winds 10 kt.
Mon..NE winds 10 kt.
Mon night..E winds 5 to 10 kt.
Tue..NE winds 10 kt.
Tue night..E winds 5 to 10 kt. Mariners are reminded that winds and waves higher in and near tstms. Unless otherwise noted, waves 1 foot or less. Charleston harbor water temperature 85 degrees.
|AMZ300 616 Am Edt Fri Jul 28 2017 |
Synopsis for the coastal waters of south coastal south carolina and north coastal georgia.. A cold front will approach the area Saturday, then move through Saturday night. High pressure will then build into the area from the northwest and persist for the first half of next week.
7 Day Forecast for Marine Location Near Hanahan, SCHourly EDIT Help
Area Discussion for - Charleston, SC  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus62 kchs 281050|
area forecast discussion
national weather service charleston sc
650 am edt Fri jul 28 2017
A cold front will approach the area Saturday, then move through
Saturday night. High pressure will then build into the area
from the northwest and persist for the first half of next week.
Near term until 6 pm this evening
Weak upper-level low pressure lurking off the georgia coast
will finally open up and eject out to the northeast this morning
in response to weak shortwave energy propagating across the
mid-atlantic states. A few showers could brush the lower south
carolina coast early, but should end shortly after sunrise.
A deep layered westerly flow will overtake the region in the
wake of the system pushing offshore, which will help delay the
inland progression of the resultant sea breeze circulation until
late afternoon. The delayed sea breeze coupled with dnva subsidence
on the backside of the departing upper low trough will tend to
limit convection despite strong insolation. Modified soundings
are fairly unstable for late july and with the region still
embedded within a ribbon of pwats near 2 inches isolated
showers tstms will remain a possibility. Will limit pops to a
broad brushed 20% area wide today with the various cams
essentially indifferent on where tstms will initiate. Could see
some localized convective enhancement occur along the sea breeze
late this afternoon, but this will be highly dependent on
whether some inland tstms can develop and push convective
outflows east to the coast. An axis of locally higher pops may
eventually be needed in subsequent forecast updates, but there
not enough confidence on how the meso-beta and meso-gamma
patterns will evolve this far out to justify higher pops at this
It will be a warm and humid day with highs poised to reach into
the lower-mid 90s inland with upper 80s to near 90 possible all
the way to the beaches. Dewpoints in the lower-mid 70s will
yield heat indices 103-106, but MAX values should remain below
heat advisory criteria of 110. The day should start out under
cloudy to mostly cloudy skies as fog and low- stratus blanket
the region, but will mix out quickly once the Sun rises. Expect
mostly sunny to partly cloudy skies to dominate for much of the
day before a thickening cirrus canopy overspreads the region
from the northwest late in the afternoon.
Short term 6 pm this evening through Monday
Tonight: a rare, mid-summer cold front will approach from the
northwest early Saturday as a deep 500 hpa trough propagating
across the great lakes phases with a cyclone meandering across
eastern quebec. 28 00z guidance suggest the bulk of the quasi-
geostrophic forcing and corridor of strongest upper difluence
will pass off the north across north carolina and northern south
carolina, but the tail end will brush area late tonight into
early Saturday. Expect most of the evening hours to remain dry,
but rain chances will be on the increase overnight as the cold
front approaches. The nam12 is the most aggressive in dragging a
line of intense pre-frontal showers tstms across much of
southeast south carolina and southeast georgia this evening and
lingering well into the overnight hours, while the GFS and
ecmwf with support from the latest nssl-wrf are much less
aggressive and several hours later. Will discount the nam12 for
now given as there could be some convective feedback mechanisms
at work and trend the forecast closer a more conservative
gfs ECMWF blended solution. Pops will range from 40-50% across
interior southeast south carolina to 10% in the savannah-darien-
ludowici corridor. Lows will range from the mid 70s inland to
around 80 at the beaches.
Saturday: an upper level trough will be establishing itself over the
east coast. The bulk of it's energy is over the northeastern states
where naefs anamolies are 2-3 standard deviations below normal for
this time of year. At the surface, a cold front will approach the
area from the northwest in the morning. Ahead of the front, deep
moisture is in place. Models show pwats approaching an impressive
2.5" while naefs indicates mean integrated WV transport about 2-3
standard deviations above normal for our area. Lift will increase in
advance of the front, aided by the exit region of a jet streak
forecasted to start moving over our area late in the day. Showers
and thunderstorms are expected ahead of and along the front,
starting inland and then moving towards the coast throughout the
day. SPC has our area under a marginal risk for severe|
thunderstorms. The limiting factor may be instability due to
abundant cloud cover. The GFS shows mlcapes peaking ~2,000 j kg far
inland late in the afternoon with showalter indices of -2 to
-4. With that in mind, a few severe storms are not out of the
question, with the main threat being damaging winds. The main
concern could be the heavy rainfall with the storms. While they
should be moving at a decent speed, if multiple storms move over the
same area flooding could become an issue, especially if they occur
around high tide in charleston, which is in the early afternoon.
Precipitation will diminish during the evening and overnight as the
front moves through the area. However, remnant showers should persist
across the coastal locations, especially south of savannah.
Sunday and Monday: models show the front becoming stationary far to
the south of our area and high pressure building in from the
northwest. Models hint at a small chance of precipitation, mainly
along the coastal locations south of savannah and the forecast
reflect this. The remaining portions of our area can expect to be
dry. Temperatures will be a few degrees below normal. But the more
noticeable feature will be dew points in the 60s, making it feel
much less humid and much more comfortable for this time of year.
Long term Monday night through Thursday
The stationary front will remain far to our south with high pressure
to our northwest. Our area should remain mostly dry through Tuesday.
By Wednesday models hint at increasing moisture across our area, and
potentially showers thunderstorms. This trend continues into
Thursday. Though, models differ on the precipitation potential. The
highest pops are along the coastal areas, especially in southeast
Aviation 12z Friday through Tuesday
Low stratus and shallow ground fog will persist at ksav through
13z before conditions rapidly improve. ExpectVFR to prevail for
much of the period at both kchs and ksav. There is a risk for
isolated tstms, but impact probabilities are still too low to
justify a mention at either terminal for the 12z TAF cycle.
Extended aviation outlook: showers and thunderstorms associated with
a cold front are expected to bring periods of flight restrictions
Saturday.VFR will return Sunday.
Today: southwest winds will increase today as a cold front draws
closer. Speeds look to stop out 10-15 kt with seas building 2 ft
nearshore with 2-3 ft offshore and charleston county waters.
Tonight: pre-frontal surging will push winds into the 15-20 kt
range overnight as the front approaches. Gust potential looks
limited in the warm flow ahead of the front, so conditions look
to remain below small craft advisory thresholds. Seas will
correspondingly build, reaching 2-3 ft nearshore with 3-4 ft
offshore and portions of the charleston county waters.
Saturday: a cold front will approach from the northwest. Ahead of
the front, southwest winds are expected. The strongest of these
winds looks to be across amz350 where the gradient will be elevated.
Gusts could approach 25 kt, mainly across the northeastern portion
of the zone in the morning and early afternoon. It's borderline
whether or not a small craft advisory will be needed. Regardless,
showers and thunderstorms are expected in the afternoon and evening.
Some of these storms could bring gusty winds. Following the storms,
winds will veer to the north northeast, with the frontal passage
Sunday through Tuesday: the front is expected to remain stationary
south of our area while high pressure builds in from the northwest.
The general wind pattern will be from the northeast, with winds
shifting to the east by Tuesday. Seas will range from 2-4 ft,
highest far offshore.
Chs watches warnings advisories
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|
|CHTS1||9 mi||46 min||W 2.9 G 6||83°F||85°F||1012.6 hPa|
|FBIS1 - Folly Island, SC||16 mi||64 min||NW 1.9 G 4.1||79°F||1013.1 hPa (+0.4)||76°F|
|41029 - Capers Nearshore (CAP 2)||18 mi||56 min||WNW 7.8 G 12||80°F||84°F||1012.4 hPa|
|ACXS1 - ACE Basin Reserve, SC||36 mi||79 min||Calm||77°F||1013 hPa||76°F|
|NIWS1 - North Inlet-Winyah Bay Reserve, SC||50 mi||79 min||W 1||77°F||1013 hPa||77°F|
Wind History for Charleston, SC(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Charleston, Charleston Air Force Base, SC||5 mi||68 min||W 4||10.00 mi||Partly Cloudy||78°F||75°F||90%||1012.6 hPa|
|Mount Pleasant Regional-Faison Field, SC||8 mi||69 min||N 0||5.00 mi||Fog/Mist||77°F||77°F||100%||1012.9 hPa|
|Charleston Executive Airport, SC||15 mi||69 min||N 0||9.00 mi||Fair||81°F||77°F||89%||1012.5 hPa|
|Moncks Corner Berkeley County, SC||20 mi||69 min||N 0||5.00 mi||Fog/Mist||73°F||73°F||100%||1012.9 hPa|
|Summerville Airport, SC||21 mi||69 min||N 0||7.00 mi||Fair||73°F||71°F||94%||1013.2 hPa|
Wind History from CHS (wind in knots)
|1 day ago||E||Calm||S||SW||NE|
|2 days ago||SW||Calm||Calm||N||W||S||S||S||W||SW||Calm||Calm||W||SW||SW||N||Calm||Calm||Calm||W||SW||NE||NE |
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Clouter Creek |
Click for Map
Fri -- 01:06 AM EDT 5.99 feet High Tide
Fri -- 06:30 AM EDT Sunrise
Fri -- 07:04 AM EDT 0.07 feet Low Tide
Fri -- 11:52 AM EDT Moonrise
Fri -- 01:45 PM EDT 5.63 feet High Tide
Fri -- 07:25 PM EDT 0.53 feet Low Tide
Fri -- 08:21 PM EDT Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Charleston Harbor Entrance |
Click for Map
Fri -- 12:42 AM EDT -0.00 knots Slack
Fri -- 03:59 AM EDT -2.34 knots Max Ebb
Fri -- 06:30 AM EDT Sunrise
Fri -- 07:13 AM EDT 0.00 knots Slack
Fri -- 09:29 AM EDT 1.45 knots Max Flood
Fri -- 11:52 AM EDT Moonrise
Fri -- 01:23 PM EDT -0.00 knots Slack
Fri -- 04:31 PM EDT -2.19 knots Max Ebb
Fri -- 07:36 PM EDT 0.00 knots Slack
Fri -- 08:20 PM EDT Sunset
Fri -- 09:43 PM EDT 1.42 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Weather Map and Satellite Images(on/off)  Help
|Weather Map ||IR Satellite Image from GEOS|
GOES Local Image of Southeast EDIT
Wind Forecast for Charleston, SC (9,2,3,4)(on/off)  Help
Ad by Google
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.