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 6:49AM||Sunset 8:06PM||Thursday August 17, 2017 1:37 PM EDT (17:37 UTC)||Moonrise 1:28AM||Moonset 3:40PM||Illumination 21%|
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|AMZ354 Waters From Savannah Ga To Altamaha Sound Ga Out 20 Nm...including Grays Reef National Marine Sanctuary- 1226 Pm Edt Thu Aug 17 2017 |
This afternoon..S winds 5 to 10 kt. Seas 2 ft. A slight chance of showers and tstms.
Tonight..SW winds 10 to 15 kt. Seas 2 ft. A slight chance of tstms. A slight chance of showers.
Fri..SW winds 5 to 10 kt, becoming S 10 to 15 kt in the afternoon. Seas 2 to 3 ft. A slight chance of tstms. A slight chance of showers.
Fri night..SW winds 15 kt. Seas 3 ft. 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. Seas 2 to 3 ft. A slight chance of showers and tstms in the morning, then a chance of showers and tstms in the afternoon.
Sat night..S winds 10 to 15 kt. Seas 2 to 3 ft. A chance of showers and tstms.
Sun..S winds 5 to 10 kt. Seas 2 to 3 ft. A chance of showers and tstms.
Sun night..S winds 5 to 10 kt. Seas 2 ft. A slight chance of showers and tstms.
Mon..S winds 5 to 10 kt. Seas 2 ft. A chance of showers and tstms.
Mon night..S winds 5 to 10 kt. Seas 2 ft. A slight chance of showers and tstms. Mariners are reminded that winds and seas higher in and near tstms.
|AMZ300 1226 Pm Edt Thu Aug 17 2017 |
Synopsis for the coastal waters of south coastal south carolina and north coastal georgia.. Atlantic high pressure will remain in control as troughing persists inland through late this week. A cold front will approach this weekend, likely falling apart early next week as high pressure returns. Another cold front will approach during the middle of the week.
7 Day Forecast for Marine Location Near Garden City, GAHourly EDIT Help
Area Discussion for - Charleston, SC  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus62 kchs 171735|
area forecast discussion
national weather service charleston sc
135 pm edt Thu aug 17 2017
Atlantic high pressure will remain in control as troughing
persists inland through late this week. A cold front will
approach this weekend, likely falling apart early next week as
high pressure returns. Another cold front will approach during
the middle of the week.
Near term through tonight
Radar continues to show showers and thunderstorms developing
across our area. Surface observations underneath this
precipitation are about ten degrees cooler. Given the increasing
coverage and the rain cooled air, we cancelled the heat
advisory. A handful of places still not yet impacted by the
convection could have heat indices remain around 110 degrees,
but this will be short lived as cold pool boundaries and or the
sea breeze move through. Most of the convection is across the
charleston tri-county and these seems to match up well with the
cams. Additionally, SPC mesoscale analysis indicates the
greatest instability here. Thermodynamics look typical for this
time of year for pulse convection.
Tonight: isolated evening or perhaps even spotty coastal nocturnal
convection is possible, as models show the upper ridge flattening
late. We played it mainly dry after midnight with another very
warm night with lows in the upper 70s most areas.
Short term Friday through Sunday
Friday: the area will lie near the southern extent of the westerlies
aloft, as deep ridging persists across the region from the
atlantic to the desert sw. The surface pattern features a well
pronounced piedmont trough and the sub-tropical ridge axis
across fl. Despite weak subsidence capping, there is adequate
instability and moisture to generate scattered convection,
mainly in the afternoon and generally triggered by the sea
breeze and small-scale boundary interactions. Pwat in excess of
2.0-2.2" and storm motion from W to E at only around 10-12 kt
will support locally heavy rain in persistent storms. The
overall thermodynamics aren't overly impressive, but with dcape
greater than 1000 j kg, strong wind gusts can occur in a few of
the tallest t-storms. Both the 925 mb and 850 mb temps remain
abnormally warm, supportive of another day with above normal
highs, at least in the lower and middle 90s prior to the onset
of convection. Associated heat indices should peak at 105- 108f,
so no heat advisory is currently anticipated.
Saturday: despite a strong short wave sweeping through the great
lakes, oh valley and upper midwest, deep ridging holds firmly in
place. The impulse aloft will push a cold front a little closer to
the area from the nw, but similar to the pattern aloft, strong
ridging will block the progress of the front from getting too close.
But due to its proximity, pwat greater than 2" and typical
instability, convective rain chances will reach at least 50%,
perhaps higher once boundary interactions, mergers, etc occur. There
is a little more shear (around 15 or 20 kt within the first 6km), so
a few multicellular clusters can occur. Moisture pooling in advance
of the front can result in a heavy rain threat, but storm motion is
a bit higher than Friday, so no widespread flooding would occur.
Again with the dcape in excess of 1000 j kg we'll need to be
concerned with some wet microburst potential a few of the storms.
Little change in low level temps and thickness values, but with a
higher rain chance, MAX temps won't be as hot as recent days, but
still above normal.
Sunday: deep sub-tropical ridging will dominate, as the cold front
fizzles out to the nw, as the sea breeze looks to be the main focus
for convection, aided by some forcing due to the rrq of the upper
jet across eastern nc and SE va. Plenty of moisture and typical
instability, will support at least chance pop's, and with less flow
than on Saturday and the high pwat's there is yet again another
locally heavy rain potential. Not much change in low level temps and
thicknesses, so MAX temps will again reach above normal prior to
Long term Sunday night through Thursday
Abnormally strong mid level ridging will prevail Monday and Tuesday
before broad long wave trough develops over a good portion of the
eastern states during the middle of the week. Simultaneously at the
surface the sub-tropical ridge will persist as a lee side trough
redevelops for Monday and Tuesday, but with diminishing heights
aloft and the formation of the large scale trough, a cold front will
attempt to approach late in the forecast period. Plenty of moisture|
and modest thermodynamics will support at least scattered coverage
of showers and t-storms through the period, including Monday, the
"big" day of the total solar eclipse. Temps will remain above august
Aviation 18z Thursday through Tuesday
MainlyVFR outside isolated to scattered afternoon and evening
showers thunderstorms. Stronger storms could generate brief
flight restrictions, but we're opting to put vcts in for now and
reserve tempos based on radar trends.
Extended aviation outlook: temporary flight restrictions can occur
in scattered and mainly diurnal convection through early next
The low level ridge axis remains well off to the south and
southeast of the waters through tonight and a typical warm
season regime of south to southwest synoptic flow will persist
over the waters. Speeds will be fairly light today with seas 2
ft or less near shore and 3 ft well offshore. Late day and
overnight surges should not amount to more than 15 kt on average
with seas still in the 2 to 3 ft range overall.
Friday through Monday: for the most part the sub-tropical atlantic
ridge will maintain its hold on the coastal waters, blocking
upstream low pressure troughs and a cold front from ever getting
this far se. At times there is enough tightening of the gradient and
a boost from the sea breeze and nocturnal low level jetting to
produce S or SW winds as high as 15 or 20 kt, but not quite enough
to reach advisory levels. Seas will top out at 3 or 4 ft. Mariners
should plan for at least isolated to scattered showers and t-storms
through the entire period.
Tides coastal flooding
Astronomical influences will lead to a round of elevated tides early
this weekend into early next week. Only small tidal departures are
necessary and we could approach shallow coastal flooding levels,
especially over parts of the sc coast, including downtown
Record high minimums for 17 august...
kchs 78 2010
kcxm 82 2010
ksav 78 1995
record high minimums for 18 august...
kchs 78 2010
kcxm 82 1998
ksav 78 2010
record high minimums for 19 august...
kchs 79 2010
kcxm 81 2009
ksav 79 1878
The temperature sensor at the downtown charleston observation site
(kcxm) has failed. Technicians are working to resolve the problem.
Temperature and dewpoint data will not be available until the sensor
Chs watches warnings advisories
long term... 33
tides coastal flooding...
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|
|FPKG1 - 8670870 - Fort Pulaski, GA||11 mi||49 min||NW 6 G 7||91°F||86°F||1017.7 hPa|
|41033||40 mi||29 min||SSW 7.8 G 9.7||87°F||1016.6 hPa|
|SAXG1 - Sapelo Island Reserve, GA||46 mi||97 min||W 1.9||93°F||1018 hPa (+0.0)||76°F|
|ACXS1 - ACE Basin Reserve, SC||48 mi||112 min||WSW 1.9||93°F||1017 hPa||77°F|
|41008 - GRAYS REEF - 40 NM Southeast of Savannah, GA||48 mi||47 min||Calm G 1.9||87°F||86°F||1 ft||1017.6 hPa (+0.0)||78°F|
Wind History for Fort Pulaski, GA(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Hunter U. S. Army Airfield, GA||3 mi||1.7 hrs||NW 6||10.00 mi||A Few Clouds||93°F||76°F||58%||1017.2 hPa|
|Savannah-Hilton Head International Airport, GA||7 mi||44 min||NW 5||10.00 mi||Partly Cloudy||95°F||75°F||53%||1017.3 hPa|
|Hilton Head Island, Hilton Head Airport, SC||24 mi||47 min||S 11||10.00 mi||Partly Cloudy||91°F||80°F||71%||1017.6 hPa|
Wind History from SVN (wind in knots)
|1 day ago||W||W||NW||NW||W||W||SW||SW||SW||W||SW||SW||SW||W||W||W||SW||SW||W||NW||W||W||W||W|
|2 days ago||SW||S||S|
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Savannah (Bull Street) |
Click for Map
Thu -- 02:28 AM EDT Moonrise
Thu -- 04:50 AM EDT 7.66 feet High Tide
Thu -- 06:50 AM EDT Sunrise
Thu -- 11:33 AM EDT -0.14 feet Low Tide
Thu -- 04:39 PM EDT Moonset
Thu -- 05:25 PM EDT 8.88 feet High Tide
Thu -- 08:05 PM EDT Sunset
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Savannah River Entrance |
Click for Map
Thu -- 02:10 AM EDT 1.57 knots Max Flood
Thu -- 02:27 AM EDT Moonrise
Thu -- 05:49 AM EDT -0.00 knots Slack
Thu -- 06:49 AM EDT Sunrise
Thu -- 09:16 AM EDT -1.80 knots Max Ebb
Thu -- 11:52 AM EDT 0.00 knots Slack
Thu -- 02:35 PM EDT 2.28 knots Max Flood
Thu -- 04:38 PM EDT Moonset
Thu -- 06:29 PM EDT -0.00 knots Slack
Thu -- 08:04 PM EDT Sunset
Thu -- 10:06 PM EDT -2.08 knots Max Ebb
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 (13,3,4,5)(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.