textproduct: Charleston

WHAT HAS CHANGED

All sections have been updated.

KEY MESSAGES

- 1) Above-normal temperatures and below-normal rain chances are expected through the upcoming weekend. Temperatures could approach the triple digits this weekend.

DISCUSSION

KEY MESSAGE 1: Above-normal temperatures build with below- normal rain chances expected through the upcoming weekend. Temperatures could approach the triple digits this weekend.

A weak front will push offshore Wednesday as Atlantic high pressure extends westward across the forecast area. Aloft, broad troughing will transition to a building ridge and increasing subsidence, limiting convection into and through the weekend. Additionally, relatively dry low and mid-level air will persist through most of the week, further suppressing convection, with no more than isolated shower or thunderstorm activity expected.

Expect near-normal temperatures behind the front on Wednesday, with a weak surface high pressure moving into the southeast before dissipating, bringing varying winds throughout the day. A gradual warming trend is forecast through the remainder of the week and into the weekend. High temperatures are expected to reach the mid to upper 90s Friday, with upper 90s becoming common across much of the area Saturday and Sunday. A few locations could even exceed 100 degrees this weekend. Combined with dew points in the 70s, heat index values could reach 108-112F, especially across the coastal counties. Additionally, since convection is forecast to be isolated, we do not expect much relief from showers/storms. While confidence in the magnitude of the heat remains limited given the forecast range, the combination of extreme heat, high humidity, and limited cooling could necessitate Heat Advisories where heat indices meet or exceed our local criteria of 108F degrees. Forecast trends will continue to be monitored over the coming days.

AVIATION /00Z WEDNESDAY THROUGH SUNDAY/

VFR conditions are expected to prevail at KCHS, KJZI, and KSAV through 00z Thursday. The main forecast issue will be changing wind directions as a front drops through from the north early Wednesday morning. West winds this evening will eventually turn north and northeast Wednesday morning, then southeast in the afternoon.

Extended Aviation Outlook: No high confidence concerns.

MARINE

Through Tonight: Winds will remain elevated but gradually weaken through the evening and overnight hours, with a weak front pushing through during the overnight hours. Behind the front, winds will turn northerly and even northeasterly. Seas will gradually improve as well, becoming 2-3 feet by sunrise Wednesday.

Wednesday through Sunday: Favorable marine conditions are expected across the local waters through the weekend. A weak front located offshore Wednesday will dissipate by Thursday as Atlantic high pressure extends westward over the region. Expect an increase in winds along the coast during the afternoon and evening periods associated with the daily sea breeze circulation. Otherwise, no marine hazards are anticipated through the forecast period.

CLIMATE

Record High Temperatures:

June 28: KCHS: 99/1998 KCXM: 100/1959 KSAV: 100/1998

Record High Minimum Temperatures:

June 23: KCHS: 78/2024 <--- record tied as of 6 AM.

June 27: KCHS: 77/2015 KSAV: 79/1952

June 28: KCHS: 78/2013 KCXM: 81/1998 KSAV: 80/1880

June 29: KCHS: 79/1977 KCXM: 83/1998 KSAV: 80/1885

CHS WATCHES/WARNINGS/ADVISORIES

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