textproduct: Columbia

WHAT HAS CHANGED

Updated Key Message to reflect the latest convective trends. Aviation discussion updated for 18z TAFs.

KEY MESSAGES

- 1. A more typical summer-like pattern expected this week.

DISCUSSION

Key Message 1: A more typical summer-like pattern expected this week.

The radar this afternoon is quickly becoming active with scattered showers and a few thunderstorms developing. This activity is forming ahead of an approaching frontal boundary still located well to the north and west of the FA. Have increased PoPs slightly with this update as coverage is more extensive than what was shown in the previous guidance. The latest SPC Outlook for today maintains a Marginal (1/5) risk for severe weather through tonight, with a Slight (2/5) risk mainly across northern Lancaster County. Damaging wind gusts would be the primary hazard from any stronger thunderstorms, although heavy rainfall and localized flash flooding will also be possible given anomalously high PWATs and long skinny CAPE profiles. Activity should diminish this evening, with another chance of rain towards daybreak as the cold front approaches.

Typical summertime conditions persist through much of the week, featuring hot and humid weather with isolated afternoon and evening convection. Brief ridging develops Wednesday before another shortwave weakness it. A surge of moisture increases on Thursday and Friday leading to higher rain chances. Ridging returns and strengthens into the upcoming weekend pushing temperatures well into the 90s, with some global models suggesting upper 90s possible early next week.

AVIATION /18Z MONDAY THROUGH SATURDAY/

Typical summer conditions expected through the afternoon, a few scattered thunderstorms possible this evening.

A typical summer day continues with scattered-broken cu around 5k feet across the region and gusty southwest winds up to 20 knots. A few isolated showers are moving across eastern GA and western SC, not enough coverage for any mentions beyond a VCSH currently. This will continue into the evening before some scattered thunderstorms are possible. It appears that the majority of the thunderstorm coverage will remain north of the TAF sites, but confidence remains high enough for a prob30 mention after 00z. Most convection will likely clear out by 06z with any restrictions lifting after. Into Tuesday, winds turn slightly more westerly by late morning, still gusty up to 20 knots with a few isolated showers-storms around.

EXTENDED AVIATION OUTLOOK...For the remainder of the week, diurnally-driven widely scattered convection is expected.

CAE WATCHES/WARNINGS/ADVISORIES

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