Marine Weather and Tide Forecast for Estill, SC

KEY MESSAGES
- 1) Dangerous heat and humidity will impact southeast Georgia and southeast South Carolina today. Extreme Heat Warnings and Heat Advisories are in effect for portions of the forecast area.

- 2) Isolated to scattered thunderstorms are expected to develop across southeast Georgia this afternoon and evening.
There will be a risk of a few strong to severe storms capable of producing damaging wind gusts, primarily along and south of Interstate 16.

DISCUSSION
KEY MESSAGE 1: Dangerous heat and humidity will impact southeast Georgia and southeast South Carolina today. Extreme Heat Warnings and Heat Advisories are in effect for portions of the forecast area.

A strong mid-level ridge will prevail over the Rockies and Plains, with the eastern periphery building into the southeastern states. A weak front will linger in the vicinity of the forecast area today. With the strong ridging aloft and the weak surface feature, temperatures will soar into the mid to upper 90s today. Dew points are forecast to reach into the mid to upper 70s, highest along the coastal corridor behind the sea breeze. This set up will yield heat index values in the 110-115 range east of I-95 and 105-110 just inland of I-95. Locations far inland will likely see heat index values top out around 103.
An Excessive Heat Warning has been issued for areas east of I-95 and south of Beaufort County, SC, with a Heat Advisory in effect north of Beaufort and just west of I-95. Heat and humidity will drop to near normal values towards the end of the week as a front approaches the region.

KEY MESSAGE 2: Isolated to scattered thunderstorms are expected to develop across southeast Georgia this afternoon and evening.
There will be a risk of a few strong to severe storms capable of producing damaging wind gusts, primarily along and south of Interstate 16.

A front is expected to gradually push southward today, becoming aligned across portions of southeast GA by the afternoon and evening. Along and south of the front, isolated to scattered thunderstorms are expected to develop. There is good agreement among the hi-res models and the 29/00z HRRR that the best chance of thunderstorm coverage will be along and south of I-16, and even moreso along and south of the Altamaha. The environment in this area is progged to have MLCAPE values upwards of 2,000 J/kg and DCAPE values of 1,000 J/kg or higher. Also, model soundings depict mid- level flow of around 25-30 knots. So the main threat will certainly be damaging wind gusts. As mentioned before the risk of thunderstorms and the severe potential increases the further south you go, especially for the counties along and near the Altamaha. To realize the severe threat, it might require storms to develop south of the Altamaha and then outflow boundaries to propagate north of the river and help to initiate new convection. The main time period of concern is roughly from 4-10pm. This area continues to be highlighted in a Marginal Risk in SPC's Day 1 Severe Weather Outlook.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/
The 12z TAF period begins with VFR conditions at KCHS, KJZI, and KSAV. Overall, VFR conditions are expected to prevail. The only real forecast concern is the potential for thunderstorms near KSAV this afternoon and evening. Current thinking is that most (if not all) activity will remain south of the terminal, but it is possible that with outflow boundary interactions that a thunderstorm could develop and get into the KSAV area in the late afternoon and into the early evening. We have maintained a PROB30 to address this potential.

Extended Aviation Outlook: Primarily VFR.

MARINE
Through tonight: West winds this morning will turn more southwest and even southerly through the evening. Wind speeds should mostly top out in the 10-15 knot range with gusts up to around 20 knots. Late tonight, A wind shift will work across the waters, turning winds more northerly or even northeasterly by sunrise Thursday. Seas will average 2-4 feet today, followed by 2-3 feet overnight.

Thursday through Monday: Southeasterly flow will dominate across the marine waters through the weekend, with gusts topping out around 10 to 15 knots through Friday. Gusts are forecast to shift to the SW and increase to 15 to 20 knots early this weekend ahead of the arrival of a cold front. The cold front is forecast to push through the region on Sunday, bringing an additional surge in winds and seas. Small Craft Advisories could be needed for portions of the marine waters for 25 knot wind gusts Sunday into Monday.

CLIMATE
Record High Minimum Temperatures:

July 29: KCHS: 80/2016 KSAV: 82/1878

August 1: KSAV: 79/2020

August 2: KCHS: 79/2022

CHS WATCHES/WARNINGS/ADVISORIES
GA...Heat Advisory from 11 AM this morning to 7 PM EDT this evening for GAZ099>101-114-115-137-216-238.
Extreme Heat Warning from 11 AM this morning to 7 PM EDT this evening for GAZ217>219-239>241.
SC...Heat Advisory from 11 AM this morning to 7 PM EDT this evening for SCZ147-149-150-152.
Extreme Heat Warning from 11 AM this morning to 7 PM EDT this evening for SCZ148-151.
MARINE...None.