Marine Weather and Tides
12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed.
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.
|Sunrise 6:33AM||Sunset 8:17PM||Monday August 3, 2020 2:16 PM EDT (18:16 UTC)||Moonrise 7:29PM||Moonset 5:15AM||Illumination 100%|
7 Day Forecast for Marine Location Near Isle of Palms, SCHourly EDIT Help
Area Discussion for - Charleston, SC  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS62 KCHS 031808 AFDCHS
Area Forecast Discussion National Weather Service Charleston SC 208 PM EDT Mon Aug 3 2020
SYNOPSIS. Isaias will bring significant impacts to our area through tonight. After the storm moves away, a stationary front will then hover over or near the area mid to late in the week.
NEAR TERM /THROUGH TONIGHT/. Early this afternoon: Radar shows that the shield of precipitation is primarily impacting an area from around Beaufort up through the Tri-County region. A loop of the radar shows that the western edge of this shield is moving very little to the west, if at all. With this in mind, the primary heavy rain area remains unchanged with significantly lower amounts to the west. We have adjusted rain chances to better account for current radar trends. A few bands and clusters of very heavy rainfall are lurking just offshore and could rotate into the Charleston County coast in the next couple of hours. Rain rates should increase significantly when this occurs and this will be when the potential for flooding issues will begin.
We continue to monitor the tornado threat, but it remains limited to coastal areas in and around the Tri-County region. The lack of instability and slightly more eastward track should keep the main threat zone over the coastal waters, but we could still see rotating storms approach and perhaps move into the coast.
Conditions will quickly improve from south to north tonight as Isaias moves away to the north with the rain ending and wind subsiding. Lows tonight should mainly be in the lower to mid 70s.
SHORT TERM /TUESDAY THROUGH THURSDAY/. Tuesday: Isaias will be far to the north of our area in the morning and continuing to quickly move away as it gets absorbed into a mid- level trough along the East Coast. Meanwhile, relatively drier air be in place across our area in the morning. Though, a cold front should approach our area from the west in the afternoon, then transition to a stationary front during the evening and overnight hours. Models indicate some sea breeze convection forming in the afternoon, with the highest probabilities across our GA counties. There doesn't appear to be much instability in place, so the severe risk is low. The convection should dissipate in the evening, then transition to the coastal waters overnight. Afternoon temperatures should peak in the 90s while overnight lows will generally be in the 70s.
Wednesday and Thursday: A mid-level trough will stretch from the Great Lakes Region down into the Deep South. Meanwhile, a stationary front will generally be just west of our area. Models are in good agreement showing a return to our typical summertime pattern. High temperatures should be in the low to mid 90s. Instability and lift from the afternoon sea breeze are expected to fire off showers/thunderstorms. Though, the details will need to be refined as this time period gets closer. Some convection could persist into the overnight hours. Lows are forecasted to be in the 70s.
LONG TERM /THURSDAY NIGHT THROUGH MONDAY/. A mid-level trough will persist over the East Coast while a stationary front hovers over or near area. The typical afternoon and evening showers and thunderstorms are expected. Temperatures should be near normal.
AVIATION /18Z MONDAY THROUGH SATURDAY/. At KCHS: Steady rain has moved into the area and ceilings have lowered into the low VFR range but visibility is solidly in the MVFR range. This steady rain will continue for the next several hours and ceilings and visibility are expected to continue lowering. The forecast has been kept in the MVFR range through the event, but we could certainly see a period of IFR conditions too. Will handle any IFR with amendments. Conditions will improve quickly later this evening as Isaias moves away from the area. Prevailing VFR conditions return around midnight and continue through the rest of the period. For winds, the peak period will arrive late this afternoon and this evening. The forecast advertises gusts to around 40 knots.
At KSAV: Steady rain is not going to make it into the terminal and we will only be dealing with occasional showers. Overall, VFR conditions are expected to prevail but there will be a period late this afternoon and evening where we could see MVFR ceilings. The forecast has been kept in the VFR range. Winds are not expected to be an issue.
Extended Aviation Outlook: Brief flight restrictions are possible within showers/thunderstorms, mainly each afternoon through Friday.
MARINE. Today and Tonight: Tropical Storm Isaias will move north through the local waters bringing dangerous marine conditions, while possibly strengthening to a minimal hurricane. Tropical Storm Warnings remain in effect for the entire area including the Charleston Harbor, although Hurricane Warnings could be needed, especially for the offshore GA waters and Charleston County nearshore waters. Conditions will also be favorable for waterspouts especially from late morning through early evening. Expect quickly improving conditions from south to north tonight as Isaias moves away to the north. We could need Small Craft Advisories in the immediate wake to at least account for residual elevated seas.
Tuesday through Saturday: Any marine headlines in effect Tuesday morning should be due to elevated seas from the storm. Though, they will quickly subside into Tuesday afternoon as the storm moves away. A stationary front is then forecasted to stay along the Southeast coast mid to late this week, leading to a return of the typical summer conditions. Winds and seas are expected to remain below Small Craft Advisory criteria during this time period.
Rip Currents: Dangerous surf conditions are expected through tonight as Isaias moves north just off the southeast Georgia and southeast South Carolina coasts. Nobody should enter the water during this time.
On Tuesday, remnant swell from the departing storm will be moving through the coastal waters. The combination of this swell, winds gradually turning onshore, and new coastal bathymetry in some areas post storm will make it easy for rip currents to form. A Moderate Risk is now in effect.
HYDROLOGY. Periods of heavy rainfall are expected today as outer bands of Isaias move inland across the area. More steady heavier rain is then likely to push into the SC coast later today into this evening and the highest total rainfall amounts are expected generally around the Charleston metro where 6 or more inches could fall. Our biggest concern is the threat for heavy rain during the evening high tide which could cause significant flooding in areas like Downtown Charleston due to the combination of freshwater and tidal flooding.
TIDES/COASTAL FLOODING. With a forecast of storm surge inundation in the 2-4 ft range, a Storm Surge Warning remains up from Edisto Beach north through the South Santee River. The best chance of seeing the peak inundation of 4 feet will be if Isaias makes landfall in our forecast area, mainly in areas just to the right/north of landfall. Where the SS Warning is in place, no Coastal Flood Advisories/Warnings will be issued, although south of the Storm Surge Warning area we will issue those products as needed. However, at this time we do not anticipate reaching major coastal flood thresholds south of Edisto Beach so a Coastal Flood Warning is unlikely. However, this could change if Isaias ends up being slower to arrive and/or stronger allowing the peak surge to better align with the high tide.
CLIMATE. Daily Rainfall Records for August 3 .
KCHS: 4.60 inches KCXM: 2.60 inches KSAV: 4.17 inches
CHS WATCHES/WARNINGS/ADVISORIES. GA . Tropical Storm Warning for GAZ116>119-138>141. High Risk for Rip Currents until 8 PM EDT this evening for GAZ117- 119-139-141. High Surf Advisory until 2 AM EDT Tuesday for GAZ117-119-139- 141. Wind Advisory until 2 AM EDT Tuesday for GAZ101. SC . Tropical Storm Warning for SCZ044-045-047>052. High Risk for Rip Currents until 8 PM EDT this evening for SCZ048>051. High Surf Advisory until 2 AM EDT Tuesday for SCZ048-051. Flash Flood Watch through late tonight for SCZ044-045-048>050- 052. Wind Advisory until 2 AM EDT Tuesday for SCZ042-043. Storm Surge Warning for SCZ049-050. High Surf Advisory until 8 AM EDT Tuesday for SCZ049-050. MARINE . Tropical Storm Warning for AMZ330-350-352-354-374.
NEAR TERM . BSH/RJB SHORT TERM . MS LONG TERM . MS AVIATION . BSH/MS MARINE . MS/RJB HYDROLOGY . TIDES/COASTAL FLOODING . CLIMATE .
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|Charleston Executive Airport, SC||171 mi||21 min||NE 8 G 15||2.50 mi||Light Rain||77°F||75°F||94%||1012.2 hPa|
Link to 5 minute data for KJZI
Wind History from JZI (wind in knots)
|1 day ago||S||S||S||S||SE||S||S||S||S||S||S||S||S||S||S||S||S||Calm||S||S||SE||SE||SE|
|2 days ago||S|
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Wind Forecast for Charleston, SC (14,3,4,5)(on/off)  Help
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