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 6:19AM||Sunset 8:35PM||Thursday June 29, 2017 11:49 AM EDT (15:49 UTC)||Moonrise 11:14AM||Moonset 11:58PM||Illumination 30%|
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|AMZ354 Waters From Savannah Ga To Altamaha Sound Ga Out 20 Nm...including Grays Reef National Marine Sanctuary- 950 Am Edt Thu Jun 29 2017 |
This afternoon..E winds 10 to 15 kt. Seas 2 to 3 ft. A chance of showers early, then a slight chance of showers and tstms.
Tonight..E winds 10 to 15 kt, becoming se 5 to 10 kt after midnight. Seas 2 to 3 ft. A chance of showers and tstms.
Fri..SE winds 5 kt. Seas 2 ft. A chance of showers and tstms.
Fri night..S winds 10 kt. Seas 2 ft. A chance of showers and tstms.
Sat..SW winds 5 to 10 kt. Seas 2 ft. A chance of showers and tstms.
Sat night..SW winds 10 to 15 kt. Seas 2 to 3 ft. A chance of showers and tstms.
Sun..SW winds 5 to 10 kt. Seas 2 to 3 ft. A chance of showers and tstms.
Sun night..SW winds 10 to 15 kt. Seas 2 ft. A chance of showers and tstms.
Mon..SW winds 5 to 10 kt. Seas 2 ft. A chance of showers and tstms.
Mon night..SW winds 5 to 10 kt. Seas 2 ft. A chance of showers and tstms. Mariners are reminded that winds and seas higher in and near tstms.
|AMZ300 950 Am Edt Thu Jun 29 2017 |
Synopsis for the coastal waters of south coastal south carolina and north coastal georgia.. High pressure to the north will pull further east this afternoon, and persist across the area into next week. A surface trough will develop inland on Friday and prevail through the weekend.
7 Day Forecast for Marine Location Near Isle of Hope, GAHourly EDIT Help
Area Discussion for - Charleston, SC  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus62 kchs 291409|
area forecast discussion
national weather service charleston sc
1009 am edt Thu jun 29 2017
High pressure to the north will move into the atlantic today,
where it will persist into next week. A surface trough will
develop inland on Friday and prevail through the weekend.
Near term through tonight
Today: shortwave ridging aloft will begin to give way this
afternoon as the baggy trough and associated mid-level low
begin to track across portions of the southeast. At the surface,
high pressure situated to the northeast will move further out
over the atlantic leaving the forecast area in a large area of
prevailing east to southeasterly low-level flow.
This onshore flow will allow for a steady moistening of the
lower troposphere today, with pwat's 1.5-2.0 inches south of the
savannah river. Further north it'll take longer for vertical
moistening, as pwat's are as low as 1.0 inches near the santee
river. Isentropic ascent on the 305k surface and a subtle mid
level perturbation that ripples through the ridge will supply
the necessary lift, with additional forcing from the sea breeze
and differential heating boundaries. Combined with the greater
moisture will support 30-50% pop's south of the savannah river,
greatest to the south of i-16. Further north there is more of a
cap and less moisture and forcing, so no more than 20-30%
chances south of the charleston tri-county, which looks to be
void of any convection through days end.
Convective temps are in the lower and middle 80s, and these
lower values have already allowed for a quick onset of showers
across parts of SE ga. We held off on mention of any thunder
until afternoon, as there isn't much instability or cape. This
is typical in a low-topped easterly flow regime, and combined
with weak lapse rates and no shear suggests that any severe risk
is close to zero.
Our 850 mb temps are still a little below late june normals, and
combined with the influx of maritime air and increasing cloud
cover will prevent temps from reaching 90f yet again.
Tonight: diurnal convection will diminish in the evening with
the loss of heating, but deep moisture will be in place in the
presence of increasing mid upper level support. This setup
should allow for more nocturnal showers and storms than we have
seen in previous nights, especially across the adjacent coastal
waters and the beaches. 30-40 percent chances are in place, but
it is likely some locations will eventually need higher values
depending on how things evolve with residual boundaries. We
could even see some fog, mainly well inland, but it has not been
added to the forecast as of yet. Increasing clouds will help
result in a warmer night with lows in the mid 70s in most
Short term Friday through Sunday
A ridge will gradually build over our area during this time
period. At the surface, high pressure will move into the
atlantic where it will persist into the weekend. Flow around the
high will allow deep moisture to advect into the area and
remain in place through the weekend. Plenty of instability will
also be in place each day. Convective initiation will mainly be
along the sea breeze corridor each afternoon. Models still hint
that a weak mid-level wave may move from the gulf of mexico over
our area late Friday. This could lead to increased convective
coverage and intensity. However, if it arrives in the evening,
following peak heating, then the effects won't be as noticeable.
Though, it could carry with it stronger storms from inland
towards our coast, which could interact with ongoing
thunderstorm outflow in our area and sea breeze circulations
during the evening hours to generate more convection. It's still|
too early to determine the details, so we have chance pops. The
typically waning of convective activity overnight is expected.
Pops on Sunday are a bit lower due to slightly lower pwat's and
instability. But we're still going to keep them in the chance
Temps will remain below normal Friday owing to onshore flow and
ample cloud cover, before returning to near normal this weekend
as a more humid airmass fills in.
Long term Sunday night through Wednesday
High pressure will prevail in the atlantic while a surface
trough persists inland. Southerly flow around the high will keep
plenty of moisture advecting into the southeast during this
time period. The result will be the typical summertime
shower thunderstorm pattern.
Aviation 14z Thursday through Monday
The first concern for the upcoming TAF period is the potential
for thunderstorms to impact ksav this afternoon. It does not
look like thunderstorms will be a concern at kchs where drier
air is in place. Most model solutions at least show
thunderstorms in the vicinity of ksav this afternoon with many
depicting a direct hit at the terminal. Introduced a tempo for
MVFR thunderstorms conditions. This will likely need to be
refined as the afternoon approaches. The next issue is the
potential for ceiling development at both sites late tonight.
Model guidance has been hinting at this for a few days now and
confidence is high enough to introduce high end MVFR ceilings at
both sites in the 07-08z time frame. There could also be some
fog around, though it is expected to be well inland if it forms
Extended aviation outlook: brief flight restrictions are
possible in afternoon showers thunderstorms at both terminals
Today and tonight: high pressure situated to the northeast will
slip further over the atlantic through the period. This will
result in a prevailing east to southeast flow through the
period. Winds this morning and afternoon will once again be
elevated, mainly around 15 knots though we could see some
periods of 15-20 knots just about everywhere. Then, as the
gradient relaxes late, wind speeds will diminish into the 10
knot range. Seas will generally range 2-3 feet, with some 4
footers possible in the outer georgia waters.
Friday through Monday: atlantic high pressure will prevail
offshore while a surface trough persists inland. The interaction
between these two features will bring the coastal waters light
to moderate breezes, with the usual summertime sea breeze wind
enhancements near the coast in the afternoon, and possible brief
periods of gusty winds around daybreak. Seas will average 2-3
ft in small southeast swell and minor local windswell.
Chs watches warnings advisories
short term... Ms
long term... Ms
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||9 mi||50 min||E 13 G 15||81°F||83°F||1022.2 hPa (+0.5)|
|41033||40 mi||42 min||E 12 G 16||82°F||82°F||1021.6 hPa|
|SAXG1 - Sapelo Island Reserve, GA||41 mi||50 min||E 7||84°F||1021 hPa (+0.0)||76°F|
|41008 - GRAYS REEF - 40 NM Southeast of Savannah, GA||41 mi||60 min||E 7.8 G 9.7||81°F||82°F||3 ft||1021 hPa (+0.6)||74°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||6 mi||1.9 hrs||E 9||10.00 mi||Partly Cloudy||84°F||72°F||68%||1020.9 hPa|
|Savannah-Hilton Head International Airport, GA||14 mi||57 min||ESE 12||10.00 mi||Overcast||85°F||70°F||61%||1021.5 hPa|
Wind History from SVN (wind in knots)
|1 day ago||Calm||SE||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||NE||NE||NE||E|
|2 days ago||N||Calm||NE||NE||E|
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Isle of Hope |
Click for Map
Thu -- 12:21 AM EDT Moonset
Thu -- 01:44 AM EDT 8.57 feet High Tide
Thu -- 06:21 AM EDT Sunrise
Thu -- 07:43 AM EDT -0.22 feet Low Tide
Thu -- 12:14 PM EDT Moonrise
Thu -- 02:29 PM EDT 7.84 feet High Tide
Thu -- 08:06 PM EDT 0.34 feet Low Tide
Thu -- 08:34 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 -- 12:21 AM EDT Moonset
Thu -- 02:00 AM EDT -0.00 knots Slack
Thu -- 05:20 AM EDT -2.39 knots Max Ebb
Thu -- 06:20 AM EDT Sunrise
Thu -- 08:09 AM EDT 0.01 knots Slack
Thu -- 10:46 AM EDT 2.16 knots Max Flood
Thu -- 12:13 PM EDT Moonrise
Thu -- 02:36 PM EDT -0.00 knots Slack
Thu -- 05:59 PM EDT -2.26 knots Max Ebb
Thu -- 08:33 PM EDT Sunset
Thu -- 08:37 PM EDT 0.00 knots Slack
Thu -- 11:13 PM EDT 2.15 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 (11,2,3,4)(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.