textproduct: Charleston

WHAT HAS CHANGED

All sections have been updated.

KEY MESSAGES

- 1) Above normal temperatures and dry conditions will prevail through Friday.

- 2) Expect gusty winds and temperatures well below normal this weekend behind a strong cold front.

DISCUSSION

KEY MESSAGE 1: Above normal temperatures and dry conditions will prevail through Friday.

Upper level ridging near the Gulf will shift northeastward over the region Thursday, as sfc high pressure lingers overhead. Thus, expect dry conditions and above normal temperatures to prevail for the remainder of the work week with the aid of sunny skies. Currently have highs in the mid to upper 80s, which is 7-9 degrees above normal for this time of year. A few locations may even take a shot at 90 degrees, which could put a few of our record highs in jeopardy (see Climate section below). Upper level pattern shifts heading into the weekend, as a strong cold front dives across the central CONUS and into our area by Saturday. Temperatures during this time will be notably cooler, as highs only rise into the upper 60s to low 70s. Overnight lows will also feel quite crisp, especially Sunday morning, as values fall into the upper 40s to 50s.

KEY MESSAGE 2: Expect gusty winds and temperatures well below normal this weekend behind a strong cold front.

A strong cold front will sweep across southeast Georgia and the SC Lowcountry late Friday night into Saturday morning. Medium range guidance generally agrees that it should be a dry cold front, only sprinkles across portions of the CHS Tri-county late Friday night into early Saturday morning. GFS H85 temperatures over Lake Moultrie cools by 10 degrees between 0Z Sat to 0Z Sun. As a result, temperature will fall well below normal on Sat, with highs ranging around 70 degrees. In addition, north-northeast winds across the region will be breezy, with gusts around 25 mph.

Saturday night into Sunday, the center of a 1035 mb high will settle over VA by daybreak Sunday. The sfc high will ridge SW across the Carolinas and Georgia on Sunday. North winds will continue through the period, generally between 10-15 mph with gusts between 20 to 25 mph. The north winds will maintain cool llvl thicknesses across the forecast area. Using a blend of guidance, low temperatures on Sunday are forecast to range from the upper 40s inland to the mid to upper 50s along the coast. High temperatures are forecast to range from around 70 degrees across the Lowcountry to the low to mid 70s across SE GA.

The center of sfc high pressure should shift over off the New England coast on Monday, resulting in winds to weaken and shift from the east. Temperatures across the CWA should warm to around seasonable normals, mid to upper 70s. Little change expected for Tuesday.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

18Z TAFs: VFR conditions continue through the evening. Latest guidance still hints that a brief period of low stratus and fog may occur prior to daybreak. Like the last issuance, have continued to carry shallow ground fog around 09z for all TAF sites. Think KSAV stands the best chance at seeing some reduced vsbys, thus, have also included a TEMPO group to account for this. Will continue to monitor trends and provide further refinements if necessary in the coming shifts. Extended Aviation Outlook: VFR.

MARINE

Tonight through Friday: High pressure will prevail across the local waters through the week and yield quiet conditions. Winds are expected to remain 10 knots or less through Thursday night. We should start to see increasing southwesterly flow Friday as a cold front approaches from the northwest. Seas should average around 2 feet through the week.

This Weekend: A strong cold front will sweep across the region late Friday night into Saturday morning. After the front late Friday night, winds will veer from the north and strength to 25 to 30 kts with gale wind gusts across the nearshore and outer SC/GA waters. Gale Watches are possible for all marine zones outside the Charleston Harbor late Friday night through much of Saturday, possibly longer across the GA waters. A Small Craft Advisory are likely for the Charleston Harbor, beginning late Friday night. As a result, wave heights are forecast to build to 7 to 10 ft on Saturday, gradually building to 8 to 12 ft by Sunday. Conditions may begin to improve early next week.

CLIMATE

Record High Temperatures:

October 13: KSAV: 90/2020

October 14: KCHS: 88/2024 KCXM: 86/2024 KSAV: 88/2024

October 15: KCHS: 87/2021 KSAV: 90/1925

October 16: KCXM: 88/2018

CHS WATCHES/WARNINGS/ADVISORIES

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