textproduct: Columbia

WHAT HAS CHANGED

Drier conditions to start the week outside of isolated showers/storms; precipitation chances increase midweek. Updated 12z Aviation.

KEY MESSAGES

- 1. Seasonal temperatures with afternoon thunderstorm chances each day this week.

DISCUSSION

KEY MESSAGE 1: Seasonal temperatures with afternoon thunderstorm chances each day into next week.

Calmer conditions are expected to settle in for Sunday as shower and thunderstorm activity shifts east toward the coastal plain. Meanwhile, drier air and some mid-level subsidence should help clear cloud cover from the Midlands and CSRA. NAEFS ensemble means suggest PWAT values falling toward the 10th percentile, generally around 1.25 inches. While a stray thunderstorm cannot be completely ruled out during peak afternoon heating, particularly along the stronger moisture gradient across the southern and eastern portions of the FA, most locations should remain dry Sunday.

Generally quiet conditions are expected through the first half of the week as a relatively dry air mass remains in place. Rain chances should stay low through Monday, with only isolated diurnally driven thunderstorms possible during the early part of the week. Moisture will gradually increase from mid to late week, resulting in a trend toward higher afternoon storm coverage. LREF probabilities indicate a 50-70 percent chance of PWAT values exceeding 1.75 inches from Wednesday onward. Upper- level troughing will also begin to shift into the region, supporting increasing moisture and greater chances for afternoon thunderstorms. Weak shortwaves embedded within the flow should also provide additional forcing for convection. Temperatures are expected to gradually warm as this overall pattern persists into next weekend.

AVIATION /12Z SUNDAY THROUGH THURSDAY/

Brief restrictions possible early with VFR conditions expected shortly after sunrise.

Patchy visibility and ceiling restrictions this morning with low level moisture in place. While brief restrictions will continue to be possible for an hour or two, moisture remains fairly shallow so improvement is expected quicker compared to yesterday. Isolated storms once again this afternoon and evening so have included a prob30 group for tsra for the Augusta terminals and OGB with highest confidence in thunderstorms affecting these terminals.

EXTENDED AVIATION OUTLOOK...Isolated storms each afternoon with higher coverage of storms expected by midweek.

CAE WATCHES/WARNINGS/ADVISORIES

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