Marine Weather and Tide Forecast for Rockville, SC

NEAR TERM /THROUGH TONIGHT/
Late this morning: No changes needed to the forecast for today.
A cold front will approach the area this afternoon. Ahead of the front, expect west-northwest downslope flow which will turn more westerly or even west-southwesterly late in the day. With plenty of insolation and temperatures warming into the upper 80s and low 90s, deep mixing will yield breezy conditions starting around midday and continuing through the afternoon. Frequent gusts into the 20-25 mph range are expected.

Tonight: A weak reinforcing cold front arrives during evening hours, remaining dry while progressing across the local area.
Sfc winds will turn more northwest post fropa with perhaps a short surge of 10-15 mph winds. However, winds are expected to become light after midnight and skies will be clear. Low temps should range in the low- mid 60s across most locations, although some upper 50s are possible across the far interior and in climatologically favored areas such as the Francis Marion Forest. Temps should remain a bit warmer along the beaches, generally in the upper 60s to around 70 degrees.

Lake Wind: Strong sfc heating along the lakeshore and warm lake water temps will favor some low-lvl mixing into 30-35 kt low- lvl wind fields this afternoon, resulting in westerly wind gusts to around 25 kt during peak heating. For this reason, a Lake Wind Advisory remains in effect from 2 PM to 8 PM this afternoon/evening.

SHORT TERM /FRIDAY THROUGH SUNDAY/
Cyclonic flow aloft will remain to the north Friday, with the Southeast U.S. positioned within the base of a trough before lifting north for the weekend. High pressure across the Central U.S. will gradually filter into the area from the northwest Friday, with additional building into Saturday. A brief, light isolated shower is possible mainly across the Charleston Tri- County area Friday as a band of vorticity sweeps the base of the trough. We introduced a small area of POPs around 15%.
Otherwise, we anticipate mostly sunny skies both Friday and Saturday. A warm front will then develop across the southern portion of the forecast area Sunday. Isentropic lift as well as some weak DCVA across the Carolinas could spawn a few showers/thunderstorms in the afternoon and evening.

Friday and Saturday will be cooler in the wake of a reinforcing cold front with highs in the low to mid 80s, although areas closer to the Altamaha River will peak in the upper 80s to around 90 degrees. Friday night will be cool as well with lows in the upper 50s to low 60s inland and upper 60s at the beaches and Downtown Charleston. Saturday night's min temps will increase by a couple of degrees. Sunday will be warmer due to southerly flow and WAA with max temps reaching the upper 80s to lower 90s away from the beaches.

LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/
The aforementioned warm front will lift north Sunday night into Monday night ahead of a developing system to the west. Rain chances will increase early next week as the warm front meanders near the area and the atmosphere becomes increasingly more conducive for a more summer-like convective pattern. Then an associated cold front is progged to sweep across the area Tuesday night into Wednesday, bringing another potential round of convection. Temperatures will return to near or slightly above normal early next week prior to the midweek FROPA.

AVIATION /14Z THURSDAY THROUGH MONDAY/
VFR conditions will prevail at CHS/JZI/SAV terminals through 12Z Friday. However, gusty west-northwest winds are expected to develop at all terminals by around 15Z this morning and peak in the 20-25 kt range during the afternoon.

Extended Aviation Outlook: Isolated showers and thunderstorms could impact the terminals Sunday.

MARINE
Today: Another gusty day is anticipated across most coastal waters with winds turning southwest this afternoon and topping out in the 15-20 kt range. Weak warm air advection is anticipated late day, suggesting some weakening of winds prior to sunset. However, the coastal waters will be along the eastern edge of enhanced low-lvl wind fields, which could support a few wind gusts near 25 kt across nearshore South Carolina waters off the Charleston County Coast mid-late afternoon. At this time, gusts do not appear frequent enough for a Small Craft Advisory. Seas will generally range between 2-4 ft, largest off the Charleston County Coast late day.

Tonight: A weak/dry cold front will arrive, shifting across local waters during the evening and perhaps early overnight period. Most guidance does not indicate a surge post fropa, with 1000mb geostrophic winds becoming rather light. However, given fropa, the latest forecast calls for southwest winds to turn more west-northwest in wake the front with a brief surge to 15-20 kt, before conditions improve late night. Seas will slowly subside with the offshore wind in place, generally to 1-3 ft.

Friday through Tuesday: There are no major concerns through the period. Offshore winds will prevail Friday with northerly winds developing early Saturday as high pressure builds from the west. Southerly winds quickly return Sunday into Tuesday as a warm front lifts northward.

CHS WATCHES/WARNINGS/ADVISORIES
GA...None.
SC...Lake Wind Advisory from 2 PM this afternoon to 8 PM EDT this evening for SCZ045.
MARINE...None.