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 7:28AM||Sunset 6:39PM||Sunday October 22, 2017 6:42 PM EDT (22:42 UTC)||Moonrise 8:58AM||Moonset 7:52PM||Illumination 8%|
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|AMZ330 Charleston Harbor- 349 Pm Edt Sun Oct 22 2017 |
Tonight..E winds 10 to 15 kt, becoming se. A chance of showers.
Mon..SE winds 15 kt. A chance of showers with a slight chance of tstms in the morning, then showers likely with a chance of tstms in the afternoon.
Mon night..S winds 15 kt. Showers with a chance of tstms.
Tue..W winds 5 to 10 kt. A chance of showers in the morning.
Tue night..W winds 5 to 10 kt, becoming nw 15 kt after midnight.
Wed..NW winds 10 to 15 kt.
Wed night..NW winds 5 to 10 kt.
Thu..NW winds 5 to 10 kt.
Thu night..W winds around 5 kt.
Fri..E winds around 5 kt.
Fri night..SE winds 5 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 73 degrees.
|AMZ300 349 Pm Edt Sun Oct 22 2017 |
Synopsis for the coastal waters of south coastal south carolina and north coastal georgia.. A cold front will push offshore Monday night and be followed by a stronger, reinforcing cold front Tuesday afternoon. High pressure will then prevail into late week before another cold front possibly affects the area next weekend.
7 Day Forecast for Marine Location Near Rockville, SCHourly EDIT Help
Area Discussion for - Charleston, SC  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus62 kchs 222020|
area forecast discussion
national weather service charleston sc
420 pm edt Sun oct 22 2017
A cold front will push offshore Monday night and be followed by
a stronger, reinforcing cold front Tuesday afternoon. High
pressure will then prevail into late week before another cold
front possibly affects the area next weekend.
Near term until 6 am Monday morning
This evening and tonight: sfc high pressure centered off the mid-
atlantic coast will lift further to the northeast and away from the
region, allowing a weak coastal trough to drift north across the
area into the evening. As the trough shifts north, strong isentropic
lift within a east southeast flow along with increasing low-lvl
moisture characterized by pwats up to 1.5-2.0 inches and sbcape
approaching 100-500 j kg should support isolated to scattered
showers this evening into early tonight over much of the area.
However, the shallow moisture depth and the speed of showers should
maintain somewhat light rainfall accumulations. Latest mesoanalysis
still hints at the possibility of a few thunderstorms over southeast
georgia early this evening, mainly for locations along and south of
i-16 where peaks of Sun are occurring and SBCAPE ranges between 1000-
1500 j kg. However, thunder chances will significantly diminish as
we approach sunset, mainly due to a lack of shear and loss of sfc
heating. Should a thunderstorm develop, a strong wind gust potential
exists given dcape values near 1000-1200 j kg over southeast georgia.
Elsewhere, shower activity along with the position of the mid upper
lvl ridge of high pressure should limit thunderstorm potential
across parts of southeast south carolina through much of the night.
As we head into overnight hours, the mid upper lvl ridge of high
pressure along the southeast coast will shift further offshore while
a longwave trough of low pressure advances over the eastern conus. A
second round of precip is expected to develop after midnight from
south to north as some mid-lvl energy travels across the area well
in advance of the approaching trough and associated cold front.
Chances of showers have been maintained for areas in southeast
georgia early tonight, before spreading northward with deeper
moisture and increasing in coverage near daybreak. We could see
widespread showers late, especially over parts of southeast georgia.
Temps will remain mild under clouds and within a southerly wind. In
general, temps should only dip into the upper 60s inland to low mid
70s closer to the coast.
Short term 6 am Monday morning through Wednesday
Monday: the day will start out with a weak warm front organizing
near the savannah river along the nose of 925-850 hpa jet.
Associated isentropic assent warm air advection will likely support
scattered to numerous showers with a few embedded tstms through the
morning, lifting into the i-26 corridor by early afternoon
coincident with the warm front. There will likely a several hours of
rain-free conditions across much of southeast south carolina and
southeast georgia after warm FROPA as the warm sector becomes more
firmly established ahead of an approaching cold front. Pops will
range from 30-70% during the morning hours with the highest pops
shifting into the charleston tri-county area by early afternoon.
Conditions will deteriorate Monday afternoon into Monday evening as
a large swath of rain moves west-east across the region. The 22 12z
gfs remains a bit more progressive than the 22 12z ECMWF and nam,
mainly due a weaker amplification of the southern steam shortwave
currently moving out of eastern oklahoma and texas. This results in
a quicker onset and progression of rain across southeast south
carolina and southeast georgia with lower qpf. Generally favored a
slower, stronger and wetter ecmwf-nam blend for timing and the
construction of hourly pops with some minor contribution from the
gfs given its continued more progressive run-to-run consistency. It
should be noted that both the NAM and ECMWF initialized better with
12z 500 hpa heights and vorticity across texas into the central
plains. Pops will range from 70-90%, highest interior southeast
georgia, Monday afternoon, 80-90% region-wide Monday evening with
rain chances ending from west-east early Tuesday morning as a cold
front pushes offshore.
Warm sector instability is expected to very slowly increase through
the day. Considerable cloudiness and some lingering shower activity
will likely limit the degree of instability somewhat, but the
combination of weak instability and increasing deep-layered quasi-
geostrophic forcing should be enough to support at least scattered
tstms. Shear will increase quickly ahead of the front, but the
limited instability should curtail the overall risk for severe
weather. If there are some unexpected breaks in the cloud canopy and
surface temperatures instability correspondingly rise, then the risk
for severe tstms could increase, especially right along the front
itself. An organized high shear low CAPE severe weather event is not
currently expected, but an isolated severe thunderstorm with
damaging winds or even a tornado can not be completely ruled out.
Highs will warm into the upper 70s well inland to the lower 80s just
inland from the coast. Lows will range from the upper 50s well
inland to the mid-upper 60s at the beaches.|
Tuesday and Wednesday: some shower activity could linger along the
charleston county coast right around sunrise, but will quickly
translate offshore. A stronger, secondary cold front will push
offshore Tuesday afternoon, delineated by a sharp 850 hpa thermal
gradient and onset of considerably stronger cold air advection.
Temperatures should rise to near 80 at the coast prior to onset of
stronger cold air advection, while far inland areas may only warm
into the mid 70s. Considerably cooler conditions will occur Tuesday
night into Wednesday with lows dropping into the mid 40s well inland
to the mid 50s at the beaches. Temperatures will only recover to the
mid 60s Wednesday afternoon as cool, canadian high pressure
dominates the region.
Long term Wednesday night through Sunday
Dry unseasonably cool conditions will prevail through Thursday
before some moderation occurs late in the week as high pressure
quickly shifts offshore allowing a milder return flow to set up.
Some uncertainty in the longer range model guidance regarding timing
of the next cold front implies lower forecast confidence starting
Friday night. For now we stayed pretty close to the latest wpc
guidance which has a cold frontal passage Saturday night into
Sunday. Temperatures will be below normal through Thursday before
likely getting back to or even above normal. Many inland areas
should get into the 40s each morning from Wednesday through Friday.
Aviation 20z Sunday through Friday
Tempo MVFR conditions are possible at the chs terminal through
21z Sunday.VFR conditions should then prevail at both terminals
early tonight before showers develop late. At this time, MVFR
conditions should prevail by 10z (potentially sooner) at the sav
terminal and persist into late Monday morning. At chs, showers
and or potentially thunderstorms should arrive late Monday
morning, but confidence in the arrival time is too low to
mention a considerable period of flight restrictions late Monday
morning into early Monday afternoon at this time.
Extended aviation outlook: MVFR with pockets of ifr or lifr (mainly
in vsbys) will occur Monday afternoon and evening as showers tstms
associated with a cold front push through. TSTM impacts are
This evening and tonight: a weak coastal trough will lift north of
the area this evening well ahead of a cold front advancing into the
eastern conus. Aloft, a mid upper lvl ridge of high pressure
centered over the western atlantic will gradually shift further
offshore as a longwave trough advances toward the region late.
Expect chances of showers and the pressure gradient to slowly
increase overnight ahead of the system. East winds will become
south late, increasing to 20-25 kts over much of the coastal
waters outside the chs harbor. Seas will also build from 3-5 ft
to 4-6 ft in nearshore south carolina waters while approaching
5-7 ft in offshore georgia waters. For this reason, small craft
advisories will begin for nearshore south carolina waters
starting at 6am Monday and will be ongoing in offshore georgia
waters tonight. Models insist on a fairly unstable marine
environment late tonight with SBCAPE approaching 1000-1500 j kg.
Given the approach of mid-lvl energy aloft, have maintained a
slight chance of thunderstorms over georgia waters after midnight.
Monday through Friday: southerly winds will help build seas to 6 ft
across mainly the south carolina nearshore waters after sunrise
Monday which will linger until Tuesday morning before subsiding as
winds turn offshore behind a cold front. A small craft advisory will
be issued for these zones to reflect this. Seas will remain above 6
ft over the georgia offshore waters until Tuesday morning as well
and an advisory remains in effect there. There is a brief window
where seas could breach 6 ft over the georgia nearshore waters,
mainly late Monday afternoon into Tuesday morning, but will defer
the need for an advisory there to the midnight shift given the event
looks marginal. Expect improved conditions Wednesday into Friday as
high pressure prevails.
Chs watches warnings advisories
Marine... Small craft advisory from 6 am Monday to 5 am edt Tuesday for
Small craft advisory until 11 am edt Tuesday for amz374.
Small craft advisory from 6 am Monday to 11 am edt Tuesday for
Near term... Dpb
long term... Rjb
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|
|ACXS1 - ACE Basin Reserve, SC||9 mi||58 min||Calm||72°F||1022 hPa||71°F|
|FBIS1 - Folly Island, SC||22 mi||43 min||E 18 G 20||75°F||1022.4 hPa (-1.2)||71°F|
|41033||23 mi||35 min||NE 3.9 G 7.8||75°F|
|CHTS1||23 mi||43 min||ENE 16 G 19||76°F||74°F||1021.9 hPa (-1.5)|
|41029 - Capers Nearshore (CAP 2)||38 mi||35 min||ESE 16 G 23||72°F||73°F||1021.7 hPa|
|FPKG1 - 8670870 - Fort Pulaski, GA||51 mi||43 min||ENE 11 G 13||74°F||74°F||1021.3 hPa (-1.0)|
Wind History for Charleston, SC(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Charleston Executive Airport, SC||17 mi||68 min||NE 5||10.00 mi||Overcast||73°F||71°F||94%||1022 hPa|
|Beaufort County Airport, SC||22 mi||68 min||ENE 9||4.00 mi||Fog/Mist||72°F||69°F||94%||1021.7 hPa|
|Beaufort, Marine Corps Air Station, SC||24 mi||47 min||E 7||1.00 mi||Fog/Mist||73°F||73°F||100%||1021.6 hPa|
Wind History from JZI (wind in knots)
|1 day ago||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||Calm||NW||Calm||Calm||N||N||NE||NE||NE||E||E||E||NE||NE|
|2 days ago||Calm||Calm||Calm||Calm||Calm||Calm||NW||Calm||Calm||Calm||N||N||N||N||N||N||N||Calm||NE||NE||E||E||SE||E |
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Steamboat Landing |
Click for Map
Sun -- 04:26 AM EDT 0.52 feet Low Tide
Sun -- 07:30 AM EDT Sunrise
Sun -- 09:57 AM EDT Moonrise
Sun -- 11:13 AM EDT 7.13 feet High Tide
Sun -- 04:59 PM EDT 0.78 feet Low Tide
Sun -- 06:39 PM EDT Sunset
Sun -- 08:52 PM EDT Moonset
Sun -- 11:19 PM EDT 6.22 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Yonges Island |
Click for Map
Sun -- 04:47 AM EDT 0.52 feet Low Tide
Sun -- 07:30 AM EDT Sunrise
Sun -- 09:57 AM EDT Moonrise
Sun -- 11:50 AM EDT 7.69 feet High Tide
Sun -- 05:20 PM EDT 0.78 feet Low Tide
Sun -- 06:39 PM EDT Sunset
Sun -- 08:51 PM EDT Moonset
Sun -- 11:56 PM EDT 6.71 feet High Tide
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 (18,4,5,8)(on/off)  Help
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