Marine Weather and Tide Forecast for James, SC

NEAR TERM /THROUGH TONIGHT/
Today: Aloft, a ridge will extend across the Southeast United States with its axis directly over the local area for much of the day. At the sfc, a stationary front will placed across South Carolina, likely just north of the local area while weak high pressure remains across the western Atlantic and eastern Gulf. The pattern will favor light southwesterly winds this morning that gradually turn more south-southwest and gust upwards to 10-20 mph this afternoon, especially closer to the coast as a sea breeze develops, then shifts inland. Much of the area will remain precip-free today, with soundings indicating a fair amount of dry air at multiple levels through the atmosphere. However, some guidance suggests h5 shortwave energy rounding the northern periphery of the ridge and helping spawn afternoon convection upstream, which then attempts to shift into northern areas (Berkeley County to Colleton County) just south of the stationary front where PWATs are locally maximized around 1.6 to 1.8 inches early afternoon. Convection that does develop upstream will likely struggle to reach the area and even more so coastal areas given substantial dry air (isolated coverage), but a stronger and/or perhaps marginally severe thunderstorm can not be ruled out given an environment marked by SBCAPE around 2000 J/kg, 0-6 km Bulk Shear around 40 kts, low-lvl lapse rates near 8-8.5 C/km and DCAPE around 1000-1200 J/kg. SPC currently marks this noted area in a Marginal Risk for severe weather as well.

Temps should be a few degrees warmer than yesterday, with 1000-850 mb thickness levels supporting highs in the low to mid 90s (warmest across Southeast Georgia). However, high clouds could once again limit heating potential and could result in minor adjustments to lowering peak temps a degree or two once trends become more clear, and especially if convection is able to reach the northern areas this afternoon.

Tonight: The mid-upper lvl ridge extending directly over the area during evening hours will shift offshore during the second half of the night as a trough progresses eastward across the Midwest. This will place a zonal flow over the local area late, well ahead of a sfc cold front advancing across the Southern Appalachians prior to sunrise. A warm airmass will be in place well ahead of this front, with little precip potential locally through the bulk of the night, but there could be a few showers entering far western locations around daybreak. Overnight lows should range in the low-mid 70s.

SHORT TERM /WEDNESDAY THROUGH FRIDAY/
Wednesday: A surface low will be positioned across Ohio with a trailing cold front swinging out across the Appalachians. Before the flow aloft becomes nearly zonal, a weak/dampening shortwave passing by to the north will help push the front across the area through the afternoon and evening hours. A narrow band of moisture with PWATS just shy of 2.0" will be present across Upstate South Carolina early morning, which will become more limited as it pushes southeastward over the forecast area. The coverage of showers/thunderstorms should diminish with time as the front encounters less net available moisture in addition to weak upper forcing. The greatest juxtaposition of instability and 850 hPa theta-e looks to occur across Southeast Georgia, so this should be where the greatest coverage of convection occurs. Pops were lowered a bit to around 15- 30%, highest south of the I-16 corridor. An isolated strong to severe storm cannot be ruled out with signs of modest instability and bulk shear values 35 to 40 kt. Rain chances will end during the evening hours as the front pushes offshore. Highs will warm into the lower 90s away from the beaches with lows ranging from the lower 70s well inland to the middle 70s at the beaches and Downtown Charleston.

Thursday and Friday: A second, reinforcing cold front could swiftly push across the area Thursday. Little moisture present due to the sweeping of the previous cold front will keep the forecast rain- free. Weak high pressure will then build into the area Friday while the flow aloft becomes slightly more cyclonic. It should feel pleasantly drier as dew points drop to around 50 degrees or lower, along with nearly full sun Friday. It will be a bit cooler Thursday behind the initial front, but still warm with highs reaching into the upper 80s away from the immediate coast. Overnight lows could touch the upper 50s far inland, but mostly in the low to mid 60s, with upper 60s along the beaches. Friday will be even cooler behind the reinforcing cold front with highs only in the low to mid 80s.

LONG TERM /FRIDAY NIGHT THROUGH MONDAY/
High pressure will extend over the area through the weekend. A weak warm front will develop and lift northward across the area Sunday into Monday night. Rain chances will return by early next week as a few showers/tstms could develop near the front. Temperatures will be at to slightly below normal into early next week.

AVIATION /09Z TUESDAY THROUGH SATURDAY/
VFR conditions will prevail at CHS/JZI/SAV terminals through 06Z Wednesday. However, south-southwest winds should gust to 15-20 kt at CHS/JZI mid to late afternoon. There is also a limited risk for an isolated shower or thunderstorm to impact CHS/JZI terminals late day, but probabilities are too low to include in the 06Z Tuesday TAF issuance.

Extended Aviation Outlook: Isolated to scattered showers/tstms are possible Wednesday afternoon.

MARINE
Today and Tonight: Weak high pressure extending across the western Atlantic and eastern Gulf will result in quiet marine conditions through the day, and likely for much of the night. In general, southwest winds this morning will gradually turn more southerly this afternoon as a sea breeze takes shape along the coast, then shifts inland. Wind speeds should top out in the 10-15 kt range for most waters, but a few gusts up to 20 kt can not be ruled out across the Charleston Harbor this afternoon. Seas will generally range between 1-2 ft during the day and evening. Late tonight, most guidance indicates the pressure gradient to start tightening, favoring an uptick in wind speeds, generally in the 15-20 kt range from the southwest. Seas will also gradually build, generally to the 2-3 ft range overnight.

Wednesday through Sunday: There are no major concerns through the period. Afternoon sea breeze surges along the land/sea interface and Charleston Harbor are possible Wednesday afternoon. Offshore winds will develop Wednesday night as a cold front pushes off the coast.
Wind gusts will briefly approach Small Craft Advisory criteria Wednesday afternoon/evening mainly across the Charleston County nearshore waters.

CHS WATCHES/WARNINGS/ADVISORIES
GA...None.
SC...None.
MARINE...None.