textproduct: Charleston

WHAT HAS CHANGED

The Aviation section was updated for the 12Z TAFs.

KEY MESSAGES

- 1) Above normal temperatures expected to impact the area during the next week. Humidity should increase late this weekend and persist into next week, especially along the coast. Heat Advisories are possible starting Sunday, then each afternoon into next week.

- 2) Typical summertime convection returns Sunday into next week.

DISCUSSION

KEY MESSAGE 1: Above normal temperatures expected to impact the area during the next week. Humidity should increase late this weekend and persist into next week, especially along the coast. Heat Advisories are possible starting Sunday, then each afternoon into next week.

A deep ridge will remain across the region today through Sunday. Early next week, H5 heights across the forecast will begin to decrease as a trough amplifies to the west. The CWA should remain east of the trough through mid next week, then zonal flow should prevail through the rest of the week. This pattern should result in above normal temperatures through this weekend into much of next week.

Independence Day: The H5 ridge over the forecast area today should result in subsidence, with forecast sounding indicating a strong inversion centered at H85. The forecast will feature dry weather with limited cloud cover. Temperatures are forecast to peak from the upper 90s inland to the low to mid 90s along the coast. The greatest heat index values should occur along the coast as dewpoints increase into the mid 70s, index values should peak around 105.

Sunday and Monday: High temperatures each afternoon are forecast to peak from the upper 90s inland to the mid 90s along the coast. Following the sea breeze, coastal dewpoints could rise into the upper 70s, with mid 70s common. Heat index values are forecast to peak around 108 along the coast, possibly prompting Heat Advisories each afternoon. The greater humidity and decreasing H5 ridging may yield isolated to scattered thunderstorms, especially along the sea breeze, each afternoon.

Above normal temperatures will persist through the rest of the work week. Low temperature may remain around record high minimums through much of the week, see Climate Section below. Afternoon convection may increase during the mid to late week, which could bring some relief from the heat.

KEY MESSAGE 2: Typical summertime convection returns Sunday into next week.

A strong ridge centered over the region will keep convection to a minimum today/Independence Day. The probability for precipitation is less than 10%. The ridge will shift offshore during the latter half of the weekend and early next week and PWats will rise back up to near or over 2 inches, allowing for a more typical summertime convective pattern to develop. Showers and thunderstorms will be possible each day, with highest coverage in the afternoons when instability is at its peak. Environment would support more pulse- like storms, with potential for a couple strong to severe storms with damaging wind gusts each day.

AVIATION /12Z SATURDAY THROUGH WEDNESDAY/

VFR conditions will prevail at CHS/JZI/SAV terminals through 12Z Sunday. Afternoon sea breeze should shift winds from the south after 17Z, winds around 10 kts.

Extended Aviation Outlook: Brief flight restrictions are possible in afternoon showers/thunderstorms late weekend into next week.

MARINE

Today through tonight: The pressure pattern should support south- southwest winds between 10 to 15 kts. Wave heights are forecast to favor 2 ft today, increasing to 2-3 ft.

Sunday through Thursday: The coastal waters will be positioned between high pressure offshore and a trough of low pressure inland much of next week. Wind speeds are forecast to stay below small craft advisory criteria through the period, however gusts in the low 20 kt range are possible, especially in the afternoon and evenings. Seas will average 2-4 feet.

CLIMATE

Record High Temperatures:

July 4: KCHS: 98/2023

July 5: KSAV: 100/1902

July 7: KCHS: 99/1954

July 10: KCHS: 100/1986 KCXM: 99/1986

Record High Minimum Temperatures:

July 5: KCHS: 78/2017 KCXM: 82/2016 KSAV: 78/2016

July 6: KCHS: 79/1990 KCXM: 82/2024 KSAV: 78/2024

July 7: KCHS: 80/2017 KCXM: 82/2022 KSAV: 80/1883

July 8: KCXM: 83/2016 KSAV: 80/1990

July 9: KCHS: 80/1998 KSAV: 80/1883

July 10: KCHS: 81/1986 KCXM: 82/1986

CHS WATCHES/WARNINGS/ADVISORIES

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