South Santee River to Edisto Beach, SC Marine Forecast
|Tonight...Sw Winds 15 To 20 Kt. Seas 3 To 4 Ft.|
|Fri...Sw Winds 10 To 15 Kt With Gusts To 20 Kt. Seas 3 Ft. A Slight Chance Of Showers And Tstms.|
|Fri Night...Sw Winds 10 To 15 Kt With Gusts To 20 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 3 Ft. A Chance Of Showers And Tstms, Mainly In The Morning.|
|Sat Night...Sw Winds 10 To 15 Kt. Seas 3 Ft. A Slight Chance Of Showers And Tstms In The Evening, Then A Chance Of Showers And Tstms After Midnight.|
|Sun...Sw Winds 10 To 15 Kt With Gusts To 20 Kt. Seas 3 Ft. A Chance Of Showers And Tstms, Mainly In The Morning.|
|Sun Night...Sw Winds 15 Kt With Gusts To 20 Kt. Seas 3 To 4 Ft. A Chance Of Showers And Tstms.|
|Mon...Sw Winds 10 To 15 Kt. Seas 3 Ft. A Chance Of Showers And Tstms.|
|Mon Night...Sw Winds 15 Kt. Seas 3 To 4 Ft. A Chance Of Showers And Tstms.|
|Tue...Sw Winds 10 To 15 Kt. Seas 3 To 4 Ft. A Chance Of Showers And Tstms.|
|Tue Night...Sw Winds 10 To 15 Kt. Seas 3 To 4 Ft. A Chance Of Showers And Tstms. Mariners Are Reminded That Winds And Seas Higher In And Near Tstms.|
|Area Forecast Discussion|
National Weather Service Charleston SC
607pm EDT Thu July 18 2019
Synopsis: Into early next week, the area will remain hot and humid between an inland trough of low pressure and Atlantic high pressure. A cold front is expected to stall over or close to the region by the middle of next week, bringing higher rain chances and somewhat cooler temperatures.
Near Term - Until 6am Friday Morning
Until Sunset: Radar shows thunderstorms far inland and along portions of the sea breeze. Storm Prediction Center Mesoscale Analysis continues to show MLCAPEs up to 3,000 J/kg ahead of these storms, which is enough energy to keep them going. Additionally, DCAPEs are around 1,000J/kg with some pockets up to 1,200 J/kg. This should lead to some marginally severe pulse storms with damaging winds. Steering winds aloft are fairly light, which is causing slow storm movements. If anything, the outflows are helping to drive their motion. With deep moisture in place (PWATs around 2"), very heavy rainfall is a concern with local flooding possible in low-lying and poorly drained areas. CAMs continue to be in good agreement showing the thunderstorms diminishing around sunset, perhaps with remnants lasting into the late evening.
Tonight: Our area will remain between Atlantic high pressure and troughing inland. Both the synoptic models and the CAMs are in good agreement showing land areas relatively dry while there is a small risk of late night showers over the coastal waters. Temperatures will remain mild.
.SHORT TERM /6am FRIDAY MORNING THROUGH SUNDAY/... Friday through Sunday: Outside any thunderstorms, heat index values will top out in the 105-109F range at many locations, and heat index values could briefly top out around 110F at some locations near the coast/just inland from the beaches as the sea breeze pushes inland.
Guidance depicts above normal Probability of Precipitation Friday afternoon/early evening, especially across southeast GA, due in part to an enhanced weakness in the upper ridge over the region. capped maximum Probability of Precipitation around 50 percent across SE GA, but locally greater Probability of Precipitation could eventually be required. In typical fashion for mid-July, a couple of pulse thunderstorms could briefly become severe with damaging wind gusts.
Saturday and Sunday: Per latest guidance, only subtle changes in the configuration of the upper ridge and inland surface trough could translate to reduced coverage of diurnal/afternoon into evening thunderstorms as compared with Friday afternoon/evening. The risk for brief/isolated damaging wind gusts will continue each afternoon/evening
Long Term - Sunday Night Through Thursday
Moderate confidence this period. The low-level lee-side trough looks to persist early in the week before deeper troughing likely moves into the area for mid week. This will mean increasing rain chances and lower temperatures, although hesitate to be too aggressive with rain chances so far out given the rarity of summertime cold fronts in this part of the country. Heat indices could still be near 110 degrees through Monday but the risk for Heat Advisories will likely be over starting Tuesday
.AVIATION /22Z THURSDAY THROUGH TUESDAY/... 18Z TAFs: VFR for much of the afternoon. Thunderstorms are expected across portions of the area from late this afternoon through early this evening. The most likely times these will occur near the TAF sites is covered by VCTS. There is a high level of difficulty determining precise flight restrictions and timing. Amendments may be made later based on radar trends and possibly to add TEMPO groups. The thunderstorms will dissipate by later this evening, allowing VFR to prevail.
Extended Aviation Outlook: VFR much of this period. Brief flight restrictions and gusty/shifting winds could occur within/near thunderstorms, especially during the afternoon/evening hours. The chance for thunderstorms/associated flight restrictions could be greatest Friday afternoon/evening and starting Tuesday as a cold front approaches the region
Tonight: The synoptic pattern will consist of high pressure in the Atlantic and a trough inland. The surface pressure gradient will become elevated the first half of the night, causing the low level jet to set up. Expect S to SW winds up to 15-20 kt with higher gusts through midnight. Winds will gradually ease during the second half of the night, as the gradient lowers slightly. Seas will be in the 2-4 ft range.
Friday through Tuesday: A typical summer pattern featuring a trough of low pressure inland and offshore high pressure will support a continuation of south/southwest winds through the period. Wind speeds will be enhanced near the coast during the afternoon/evening from the sea breeze and across coastal waters during the overnight. Through this weekend, winds should remain capped around 20 knots and seas should;d average 2-4 feet, below Small Craft Advisory levels. Early next week, a cold front will approach the region, and the probability for local Small Craft Advisory conditions could increase
NOAA Charleston SC Office: Watches - Warnings - Advisories
GA...None. SC...None. MARINE...None