textproduct: Charleston

WHAT HAS CHANGED

The Aviation Section has been updated for the 18Z TAF issuance.

KEY MESSAGES

- 1) Quiet weather and warming temperatures into Monday.

- 2) A strong backdoor cold front will yield breezy winds and cooler conditions mid-week.

DISCUSSION

KEY MESSAGE 1: Quiet weather and warming temperatures through the weekend.

Surface high pressure will remain the dominant synoptic feature while aloft, a weak shortwave ripples across the southeastern states. CAMs remain in agreement that this shortwave could trigger some showers and maybe a thunderstorm, mainly across the SC Midlands. The current forecast for the SC Lowcountry and SE Georgia remains dry, however a stray weak shower could impact far inland Berkeley County this evening. High temperatures will be roughly 10 degrees above normal through the weekend and into Monday, with highs reaching into the 80s.

KEY MESSAGE 2: A strong backdoor cold front will yield breezy winds and cooler conditions mid-week.

A strong backdoor cold front will push through the region Monday night/Tuesday morning. In the wake of the front, breezy conditions will develop, especially along the coastal counties. The NBM has increased in its probabilities of wind gusts >25 mph along the coastal counties, now showing around 60% on Tuesday. While high temperatures Tuesday will be much lower than the previous few days, highs will generally be around normal for this time of year in the upper 60s to low 70s. Meaningful rainfall with this backdoor cold front is not expected, with PoPs topping out only around 30% Tuesday night and Wednesday. A return to above normal temperatures arrives Thursday as high pressure builds into the region again.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

VFR conditions will prevail at KCHS, KJZI, and KSAV through 18Z Sunday.

Extended Aviation Outlook: Prevailing VFR through Monday. A backdoor cold front will push through the terminals Monday evening into Tuesday morning bringing showers and thunderstorms. In the wake of the front on Tuesday, winds will shift to the NE and gust 20 to 25 knots.

MARINE

Prevailing high pressure this weekend and into Monday will yield sub- Small Craft Advisory conditions across all waters.

Monday evening a backdoor cold front is poised to push southward across the marine zones. The combination of cooler temperatures and a tightening pressure gradient will yield gusty NE winds and building seas Monday night into Wednesday morning. Wind gusts could reach Gale criteria across waters outside of the Charleston Harbor early Tuesday morning. A Gale Watch could be required for these waters. Small Craft Advisory conditions are forecast in the Charleston Harbor, with NE gusts of 25 knots.

High pressure will build into the region mid-week, with decreasing winds and diminishing wave heights. 6 ft seas may linger in the 20 to 60 nm offshore GA waters into Wednesday.

CLIMATE

Record High Temperatures:

March 22: KCHS: 88/2011

March 23: KCHS: 87/1995

March 27: KCHS: 87/2021 KCXM: 81/2021 KSAV: 89/2021

CHS WATCHES/WARNINGS/ADVISORIES

GA...None. SC...None. MARINE...None.