textproduct: Charleston

WHAT HAS CHANGED

Updated the Aviation section for the 00Z TAFs. The threat for severe weather has ended across the area, and its key message was removed. Tide levels along the Charleston/Colleton County coasts have fallen short of reaching minor coastal flood stage, and the Coastal Flood Advisory was cancelled.

KEY MESSAGES

- 1) Showers and thunderstorms expected to continue into early next week with a persistent summertime pattern.

- 2) Minor coastal flooding possible along the Charleston and Colleton County coasts during the evening high tide Monday.

DISCUSSION

KEY MESSAGE 1: Showers and thunderstorms expected to continue into early next week with a persistent summertime pattern.

A classic early-summer pattern will remain established across southeast South Carolina and southeast Georgia through early next week. Atlantic high pressure will remain anchored offshore while mid- lvl ridging across the western Atlantic periodically interacts with embedded shortwave perturbations rotating around the ridge periphery. Low-lvl flow remains generally south to southwest, maintaining a rich maritime tropical airmass through next week. This pattern will yield afternoon showers and thunderstorms each afternoon and evening.

Similar to last couple of days, forecast soundings indicate PWAT values ranging from 1.9 to 2.3 inches through the period (near the 90th percentile for mid-June). This combined with surface dewpoints in the low to mid 70s should yield SBCAPE values between 2500-3000 J/kg amid peak heating. Mid-lvl lapse rates remain relatively modest with values ranging from 5.5-6.0 C/km, suggesting pulse-type convection will dominate through the period. Expect the afternoon seabreeze to push inland each day and collide with other outflow boundaries, yielding the primary focus for convection initiation.

As we head into early to mid-week, broad mid-lvl troughing will likely encompass the eastern half of the CONUS. At the surface, a weak cold front will approach the region on Monday, and then push offshore by Tuesday evening. Convection coverage will likely increase from late morning near the coastline before expanding more inland in the afternoons. Highest PoPs will likely occur along and west of I-95 corridor where seabreeze interactions maximize.

This pattern should remain active into the end of the week as this broad mid-lvl troughing continues aloft, with another cold front moving towards the area by late week/early weekend.

KEY MESSAGE 2: Minor coastal flooding possible along the Charleston and Colleton County coasts during the evening high tide Monday.

Breezy south-southwesterly winds along with the lunar Perigee (June 14th) and New Moon (June 15th) could result in elevated tidal departures Monday, setting the stage for possible minor coastal flooding along the Charleston and Colleton County coasts during the evening high tide. Coastal Flood Advisories could be needed for the Charleston and Colleton county coastlines.

AVIATION /00Z MONDAY THROUGH FRIDAY/

15/00Z TAF Discussion: Overnight, conditions should remain VFR with slightly elevated SW winds. A second round of showers/thunderstorms could approach the terminals tonight after midnight, but there is moderate confidence in thier decay before reaching the terminals. No mention of impacts in the TAFs for now.

Extended Aviation Outlook: VFR conditions expected to prevail at CHS/JZI/SAV terminals. However, brief flight restrictions are possible with afternoon showers and/or thunderstorms through the middle of this week.

MARINE

Tonight through Monday, the pressure pattern will support southwest winds between 10 to 15 kts with gusts in the lower 20s. Wave heights are forecast to remain between 2 to 4 ft. Winds should generally continue tonight into Monday.

Tuesday through Friday: Expect generally south-southwesterly winds with speeds ranging from 15 to 20 kts with gusts up to 22-24 kts as Atlantic high pressure persists across the local waters. There could be the need for Small Craft Advisories for Thursday evening into Friday ahead of an approaching cold front. Seas should remain below 6 feet throughout the period.

Rip Currents: A Moderate Risk of rip currents is forecast Monday along the southeast South Carolina and southeast Georgia beaches given the combination of elevated winds and a lingering south-southwesterly swell.

CLIMATE

Record High Temperatures:

June 15 KCHS: 98/2015

Record High Minimum Temperatures:

June 14 KCHS: 79/2010 KCXM: 81/2010

June 15 KCHS: 80/2010

June 18 KCHS: 78/2015

June 19 KCHS: 79/2025 KCXM: 81/2025 KSAV: 79/1881

CHS WATCHES/WARNINGS/ADVISORIES

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