South Santee River to Edisto Beach, SC Marine Forecast
|Tonight...Sw Winds 5 To 10 Kt. Seas 2 Ft.|
|Tue...Sw Winds 10 To 15 Kt, Becoming Nw 20 To 25 Kt With Gusts To 35 Kt In The Afternoon. Seas 2 To 3 Ft, Building To 3 To 4 Ft In The Afternoon. A Chance Of Showers In The Morning, Then Showers In The Afternoon.|
|Tue Night...N Winds 25 To 30 Kt With Gusts To 40 Kt. Seas 4 To 6 Ft, Building To 5 To 7 Ft After Midnight. Showers In The Evening.|
|Wed...Ne Winds 20 To 25 Kt. Gusts To 35 Kt In The Morning. Seas 5 To 7 Ft, Subsiding To 4 To 6 Ft In The Afternoon.|
|Wed Night...Ne Winds 15 To 20 Kt. Seas 4 To 6 Ft, Subsiding To 4 To 5 Ft After Midnight. A Slight Chance Of Showers.|
|Thu...Ne Winds 10 To 15 Kt. Seas 4 To 5 Ft, Subsiding To 3 To 4 Ft In The Afternoon. A Chance Of Showers.|
|Thu Night...Ne Winds 5 To 10 Kt. Seas 3 To 4 Ft. A Chance Of Showers.|
|Fri...N Winds 15 To 20 Kt. Seas 3 To 4 Ft. A Chance Of Showers.|
|Fri Night...N Winds 20 To 25 Kt. Seas 4 To 6 Ft. A Chance Of Showers.|
|Sat...N Winds 20 To 25 Kt. Seas 5 To 7 Ft. A Chance Of Showers.|
|Sat Night...N Winds 20 To 25 Kt. Seas 5 To 7 Ft. A Chance Of Showers.|
Area Forecast Discussion|
National Weather Service Charleston SC
351pm EST Monday Nov 11 2019
High pressure across the region will weaken tonight. A strong cold front will sweep across the area Tuesday, before high pressure returns and prevails through Thursday. A series of low pressure systems could impact the region this weekend into early next week.
Near Term - Until 6am Tuesday Morning
Surface high pressure will continue moving farther off the coast tonight while a cold front steadily approaches from the west. Increasing mid and high level cloudiness overnight will result in considerably warmer overnight temperatures compared with last night. Low temps will be in the low to mid 50s.
Short Term - 6am Tuesday Morning Through Thursday
Tuesday: Based on a blend of the short range guidance, the leading edge of a wide band of showers will reach the inland counties around sunrise Tuesday. The showers are timed to slide east during the daylight hours, peaking in coverage and intensity during the early to mid afternoon hours. Probability of Precipitation will peak near 100 percent for most areas on Tuesday, with Quantitative Precipitation Forecast values ranging around a quarter of an inch. Given the timing of the thick cloud cover and showers, high temperatures should favor values in the mid to upper 60s. The arrival the cold air advection late Tuesday afternoon with winds veering from west to north. BL mixing will remain to at least 2 kft and momentum transfer should support gusts into the mid 20 kts by late Tuesday afternoon. I will highlight the wind potential with a Lake Wind Advisory for Lake Moultrie for Tuesday afternoon through Tuesday night. See Marine Section for Gale and Small Craft headlines.
Tuesday night: Gusty north winds will develop in the wake of the cold front, strongest during the evening hours. H85 temps will cool through most of the night, reaching 2C across the inland counties to 3-4C along the coast during the pre-dawn hours. Using a blend of the cooler MOS members, I will forecast low temperatures to range from the upper 20s inland to the low to mid 30s along the coast. These temperatures should range very close to record low values, see the Climate section below. I will highlight the cold temperatures with a Freeze Watch from Tuesday evening through mid-morning Wednesday.
Wednesday: The center of surface high pressure will slide over the mid- Atlantic states during the day. Ridging high pressure will support steady or low end gusty NE winds across the CWA. The LLVL flow will keep H85 temps steady in the single digits through the day. Despite nearly full sun, high temperatures are expected to remain limited to around 50 for most areas. In fact, high temperatures are forecast to challenge the record low maximums at KCHS, KCXM, and KSAV.
Thursday: Low temperatures should begin the day around 3 to 5 degrees warmer than values observed on Wednesday morning. The temperatures remain a little warmer due to increase cloud cover arriving from the east. GFS indicates an inverted trough off the coast of FL during the morning lift north along the coast through the day, reaching the GA/SC coast by the afternoon. Guidance indicates that most of the associated showers will remain across the coastal waters for most of the day. However, isolated to scattered showers may spread onshore during the afternoon and evening hours. High temperatures are forecast to range in the mid to upper 50s.
Long Term - Thursday Night Through Monday
Low pressure should develop and strengthen near or just off the Southeast coast Thursday night into Friday, suggesting scattered showers across the area that gradually decrease in coverage into Saturday as the low departs to the northeast. High pressure should then remain somewhat wedged across the area on Sunday, favoring mainly dry conditions across inland areas while a few showers potentially impact locations along the coast. Large model spreads indicate greater uncertainty in the forecast early next week, but the general consensus is that more low pressure will impact the region with the potential of scattered to numerous showers across the Southeast United States.
Temps should be slightly more mild over the weekend and early next week with highs generally ranging in the low/mid 60s. Overnight lows should initially dip into the low/mid 40s away from the coast this weekend, then into the upper 40s/lower 50s early next week.
A very weak pressure gradient will persist through tonight as surface high pressure weakens and shifts farther east.
A cold front will sweep across the region on Tuesday, gusty NW winds are expected during the late afternoon and evening hours. Short term guidance indicates that winds will strengthen to gale force with the arrival of Cold Air Advection Tuesday afternoon until Wednesday morning. Given the strengthening winds, seas should build to 3-7ft within 20 NM, with up to 10 ft possible across the outer GA waters. I have issued a Gale Warning for the marine zones outside the Harbor from Tuesday afternoon until 7AM Wednesday, I will post a Small Craft Advisory for the CHS Harbor until noon Wednesday. After the Gale Warning period, conditions will likely warrant a Small Craft Advisory for the nearshore waters through Wednesday and the outer GA waters into Thursday morning.
Winds/seas should improve and remain below Small Craft Advisory levels Thursday while a coastal trough develops off the Southeast coast, but conditions should once again deteriorate heading into Friday evening and night as a low pressure system passes near the Southeast coast. Small Craft Advisories could be needed for most waters during the weekend.
Tides / Coastal Flooding
The combination of astronomical forces and periods of gusty northeast winds will result in elevated tide levels through Thursday. On Tuesday, primarily due to the occurrence of the full moon, the high tide along the lower SC coast may approach flood stage. In the wake a strong cold front, gusty north-northeast winds are expected along the entire coastline Tuesday night into Wednesday. The strong winds will likely result in a surge of water, resulting in tidal departures around 1.5 ft, forecast to result in moderate coastal flooding. Persistent northeast winds will linger into Thursday morning, expected to maintain tidal departures between 1-1.5 ft, with minor to moderate coastal flooding expected. Coastal Flood Advisories appear likely along the entire coastline of the forecast area on Wednesday morning and again Thursday morning.
TEMPERATURE RECORDS FOR 11-13 STATION RECORD LOW HIGH RECORD LOW ------- ---------------- ------------ KCHS 51 2013 29 1941 KSAV 50 1920 29 1968 KCXM 49 1920 34 1968
NOAA Charleston SC Office: Watches - Warnings - Advisories
GA...Freeze Watch from Tuesday evening through Wednesday morning for GAZ087-088-099>101-114>119-137>141. SC...Freeze Watch from Tuesday evening through Wednesday morning for SCZ040-042>045-047>052. Lake Wind Advisory from 4pm Tuesday to 7am EST Wednesday for SCZ045.
Gale Warning from 4pm Tuesday to 7am EST Wednesday for AMZ350-352-354-374. Small Craft Advisory from 4pm Tuesday to noon EST Wednesday for AMZ330.