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 6:48AM||Sunset 7:56PM||Wednesday August 23, 2017 4:14 AM EDT (08:14 UTC)||Moonrise 7:39AM||Moonset 8:22PM||Illumination 1%|
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|AMZ330 Charleston Harbor- 334 Am Edt Wed Aug 23 2017 |
Today..SW winds 5 to 10 kt, becoming S 10 to 15 kt. A slight chance of showers and tstms.
Tonight..SW winds 10 to 15 kt. A chance of showers and tstms.
Thu..SW winds 5 to 10 kt. A chance of showers and tstms in the morning, then showers and tstms likely in the afternoon.
Thu night..S winds 5 kt, becoming nw around 5 kt after midnight. A chance of showers and tstms.
Fri..NE winds 5 to 10 kt. A chance of showers and tstms.
Fri night..NE winds 10 kt. A chance of showers and tstms.
Sat..NE winds 10 to 15 kt. A chance of showers and tstms.
Sat night..NE winds 10 to 15 kt. A slight chance of showers and tstms.
Sun..NE winds 10 to 15 kt. A chance of showers and tstms.
Sun night..NE winds 10 to 15 kt. A chance of showers and tstms. Mariners are reminded that winds and waves higher in and near tstms. Unless otherwise noted, waves 1 foot or less. Charleston harbor water temperature 87 degrees.
|AMZ300 334 Am Edt Wed Aug 23 2017 |
Synopsis for the coastal waters of south coastal south carolina and north coastal georgia.. High pressure will give way to an approaching cold front through tonight. The cold front is expected to pass over the region on Thursday. A wave of low pressure could form along the front offshore Friday, as high pressure builds from the north next weekend.
7 Day Forecast for Marine Location Near North Charleston, SCHourly EDIT Help
Area Discussion for - Charleston, SC  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus62 kchs 230759|
area forecast discussion
national weather service charleston sc
359 am edt Wed aug 23 2017
High pressure will give way to an approaching cold front
through tonight. The cold front is expected to pass over the
region on Thursday. A wave of low pressure could form along the
front offshore Friday, as high pressure builds from the north
Near term through tonight
Pre-dawn: mainly clear weather with a light southwest synoptic
flow across the region. Along the land breeze adjacent to the
sc coast, isolated showers or a TSTM could develop nearing dawn
perhaps brushing some of the near coastal areas of charleston
county. Temps in the mid 70s many areas over the next few hours.
Today: the mid upper level ridge is forecast to gradually erode
as troughing builds to our north. A piedmont surface trough is
forecast to become better defined over the csra and sc midlands
while a cold front gets hung up in the mountains later today.
The morning hours should mainly be dry with an offshore component
in the boundary layer flow. This initial pattern with morning
sunshine and weak downslope suggests it will warm 2-3 degrees
from Tuesday's afternoon readings at many locations. Soundings
indicate a 2c-3c cap which is forecast to deteriorate by 18z at
most locations. Since the sea breeze will be a slow mover this
afternoon, most of the low level moisture convergence and dew
point pooling looks to arrive along and to the west of i-95
around 21z. This time frame is when most models paint the
higher axis of 850 mb theta-e across the forecast area. There is
a slight uptick of mid upper flow to the north of i-16 later
today and tstms should have an E or ese translation. Convective
boundaries could collide with the sea breeze late, resulting in
isolated stronger storms with enhanced updrafts due to steep low
level lapse rates. We maintained 30 pops after mid afternoon
into the late day hours for just about all zones. Highs in the
Tonight: the cold front will sag into the inland carolinas and north
ga overnight. Slightly deeper moisture will pass through the region
while models indicate increasing upper difluence across the area
in the rear entrance region of a 50-60 knot 250 mb jet arcing
from the mid atlantic to the western carolinas. Scattered convective
rains are possible with this setup, despite the loss of diurnal
heating and persistent poor mid level lapse rates. We maintained
lower end chance pops for the overnight, especially sc zones where
we show some 50 percent pops at times.
Short term Thursday through Saturday
Thursday and Friday: the cold front will slowly cross through the
forecast area before crossing offshore Thursday night. Higher
coverage of convection is anticipated Thursday relative to previous
days given the focusing mechanism provided by the front itself.
Pwats will exceed 2 inches with sbcapes climbing above 2000 j kg,
suggesting locally heavy rainfall as a primary hazard. Greatest
precipitation chances will generally shift east and ultimately into
the coastal waters along with the front as surface pressures rise
behind. Near-normal temperatures are expected.
Saturday: the front will stall well offshore late Saturday. Model
guidance continues to indicate low pressure may begin to form on the
tail end of the stalled front by late Saturday or early Sunday.
Locally, a less active day looks likely, with greatest potential for
precipitation primarily confined to the coastal waters, though some
shower thunderstorm activity near the coast is possible.
Temperatures will likely be just below normal values.
Long term Saturday night through Tuesday
Surface high pressure will continue to reach into the area from|
canada. Fairly reasonable model agreement depicts a coastal low
developing off the ga sc coast by late this weekend. In addition,
guidance suggests that the remnants of harvey will track towards the
forecast area from south texas. At least some degree of wedging of
the high pressure over the carolinas seems probable with low
pressure to the east and west, resulting in a cloudy and potentially
unsettled period. Daytime warming would be tempered in this regime,
with highs averaging in the mid-80s appearing reasonable at this
time. By Tuesday, deeper moisture may provide greater coverage of
convection, but model solutions diverge considerably by this time,
increasing forecast uncertainty.
Aviation 08z Wednesday through Sunday
Vfr. Risk for late afternoon showers tstms impacting either
kchs or ksav Wednesday remains too low to justify a mention at
either terminal, especially since the potential timing window
Extended aviation outlook: thunderstorms may result in short periods
of flight restrictions, mainly each afternoon evening. Numerous
thunderstorms are expected along and ahead of a cold front Thursday.
Through tonight: winds will mainly be from the ssw and sw
between high pressure offshore and an approaching cold front.
The gradient will continue to tighten through this evening and
wind speeds will peak between 15 and 20 knots for a period from
late today into the early morning, unless any convection or
convective boundaries moving offshore disrupt the synoptic wind
flow. Winds will gradually diminish late tonight as the cold
front nears from the NW and n. Seas will range from 2 to 4 ft
offshore to 4-5 ft out near the gulf stream.
Thursday through Monday: south to southwest flow generally 10-15
knots expected through Thursday night as a weak cold front crosses
through the area. Flow will veer northeast on Friday and strengthen
through early next week as high pressure builds while low pressure
appears poised to develop along the offshore cold front. Winds and
seas will steadily increase from Friday night through Monday, with
small craft advisory conditions increasingly likely by Saturday
afternoon or night. The low pressure system is currently forecast to
make its closest approach next Monday into Tuesday, potentially as a
Rip currents: a 2-3 ft swell every 9-10 seconds will continue
today. This combined with fairly decent onshore flow in the
afternoon will yield a moderate risk for rip currents along the
charleston county beaches today.
The kclx radar is operational, but additional outages are likely
as more parts are replaced.
The temperature and dew point sensors at the downtown charleston
observation site (kcxm) could periodically fail. Parts are on
order and technicians will attempt to resolve the problem once
Chs watches warnings advisories
short term... Jmc
long term... Jmc
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||8 mi||45 min||SW 4.1 G 5.1||81°F||87°F||1014.7 hPa|
|FBIS1 - Folly Island, SC||14 mi||75 min||SW 11 G 14||83°F||1015.2 hPa (-1.0)||75°F|
|41029 - Capers Nearshore (CAP 2)||23 mi||67 min||SW 16 G 19||82°F||86°F||1014.4 hPa|
|ACXS1 - ACE Basin Reserve, SC||29 mi||90 min||Calm||80°F||1015 hPa||78°F|
|41033||44 mi||67 min||SW 12 G 16||84°F||1014.5 hPa|
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||4 mi||19 min||SW 5||10.00 mi||Partly Cloudy||77°F||75°F||96%||1014.2 hPa|
|Charleston Executive Airport, SC||11 mi||20 min||N 0||10.00 mi||Fair||81°F||75°F||84%||1014.6 hPa|
|Mount Pleasant Regional-Faison Field, SC||15 mi||20 min||N 0||9.00 mi||Partly Cloudy||79°F||77°F||94%||1014.2 hPa|
|Summerville Airport, SC||19 mi||20 min||N 0||10.00 mi||Fair||73°F||73°F||100%||1014.6 hPa|
|Moncks Corner Berkeley County, SC||23 mi||20 min||SW 4||10.00 mi||Fair||75°F||73°F||94%||1014.2 hPa|
Wind History from CHS (wind in knots)
|1 day ago||Calm||NE||N||Calm||N||NE||E||E||SE||E||N|
|2 days ago||Calm||Calm||Calm||Calm||W||SW||N||Calm||S||SE||E||S||SE||S||S||SE||S||Calm||Calm||Calm||Calm||Calm||Calm|
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
Click for Map
Wed -- 04:24 AM EDT -0.28 feet Low Tide
Wed -- 06:49 AM EDT Sunrise
Wed -- 08:38 AM EDT Moonrise
Wed -- 10:37 AM EDT 6.48 feet High Tide
Wed -- 04:39 PM EDT -0.31 feet Low Tide
Wed -- 07:55 PM EDT Sunset
Wed -- 09:22 PM EDT Moonset
Wed -- 10:52 PM EDT 6.87 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Charleston Harbor Entrance |
Click for Map
Wed -- 01:12 AM EDT -3.00 knots Max Ebb
Wed -- 04:20 AM EDT 0.00 knots Slack
Wed -- 06:37 AM EDT 1.73 knots Max Flood
Wed -- 06:48 AM EDT Sunrise
Wed -- 08:37 AM EDT Moonrise
Wed -- 10:29 AM EDT -0.00 knots Slack
Wed -- 01:35 PM EDT -2.84 knots Max Ebb
Wed -- 04:35 PM EDT 0.00 knots Slack
Wed -- 06:53 PM EDT 1.87 knots Max Flood
Wed -- 07:54 PM EDT Sunset
Wed -- 09:21 PM EDT Moonset
Wed -- 10:45 PM EDT -0.00 knots Slack
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 (4,6,7,8)(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.