textproduct: Charleston

WHAT HAS CHANGED

Issued a Small Craft Advisory for the coastal waters from South Santee River, SC to Edisto Beach, SC out 20 nautical miles. Elsewhere, no major changes coming down the track this forecast cycle.

KEY MESSAGES

- 1) The next frontal system will bring widespread rainfall late Thursday through Friday.

DISCUSSION

KEY MESSAGE 1...The next frontal system will bring widespread rainfall late Thursday through Friday.

Trough gradually deepens across the Mid- and Deep-South Thursday, moving eastward towards the Coastal Empire and Lowcountry by Thursday night. This will help push a surface cold front into the area, providing sufficient lift for rain. Rich southerly flow starts developing as early as Wednesday evening, pumping more moisture into the area. Spotty showers start developing inland by Thursday morning where some better forcing persists in the lower levels. The bulk of the energy in the upper levels doesn't arrive until Thursday night, where the radar will really start to fill in with rain. This continues well into Friday. Confidence is still shaky as to when the rain tapers off. As the front slows down, coastal showers may persist into Saturday afternoon. Drought conditions continue, which protect the area from any flooding issues. Could see some beneficial rain here, with amounts up to an inch possible.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

Nothing but VFR through the 18Z TAF period. Light NNW breeze will gradually back to the SSW to SW this evening and overnight. Gradient winds start to pick up after sunrise Wednesday morning, with gusts up to 20-22 kts towards the end of the period.

Extended Aviation Outlook: VFR conditions likely to persist through at least Thursday. A front should bring flight restrictions late Thursday night into Friday. Occasional flight restrictions could persist into Saturday. Conditions should improve back to VFR Saturday night through Sunday.

MARINE

This Afternoon and Tonight: High pressure will gradually slide east across the Atlantic this afternoon into tonight, favoring winds and seas that remain below Small Craft Advisory levels across all local waters. There are some hints of the pressure gradient intensifying late night as troughing passes to the north, which could support southwest winds gusting up to 20-25 kt within a few hours of daybreak while seas build up to 3-5 ft.

Wednesday: Small Craft Advisory now in effect starting at 7 AM EST for the coastal waters from South Santee River, SC to Edisto Beach, SC out 20 nm. Southwesterly winds increase in response to a re-tightening of the pressure gradient. Also, with some south-southwesterly swell building into the waters, there is a possibility of some 6 footers reaching into the nearshore Charleston waters and offshore Georgia waters on Wednesday as well. The signatures are just not strong enough to warrant an advisory in those areas at this time.

Thursday and Friday: An approaching cold front from the west on Thursday will yield elevated winds and seas across most of the local waters and conditions will likely warrant the need for Small Craft Advisories on Thursday into Friday. South- southwesterly swell should build into the local waters again on Thursday morning and seas will range from 4 to 6 ft through early Friday morning. Expect the front shifts offshore by Friday night and marine conditions subside.

CHS WATCHES/WARNINGS/ADVISORIES

GA...None. SC...None. MARINE...Small Craft Advisory from 7 AM Wednesday to 7 AM EST Thursday for AMZ350.