textproduct: Columbia

SYNOPSIS

A mix of sun and clouds are expected today where a few showers or thunderstorms will be possible later this afternoon and into the evening hours as a weak frontal boundary stalls out in the area. The region will then begin to transition to a more summerlike pattern, with less organized and more typical pulse convection through the remainder of the week and into next weekend.

NEAR TERM /THROUGH TONIGHT/

Key Message(s):

- Area of shower/storms this morning across northern Midlands into Pee Dee Region.

- Scattered convection expected mainly in the eastern Midlands this afternoon.

Early morning radar shows a batch of disorganized showers and embedded thunderstorms across the northern Midlands, trailing just east of Atlanta. This is in response to a shortwave pivoting into the region as well as a slow moving cold front that is now entering the upstate of SC and into northern GA. PWAT's generally remain between 1.6-1.7" across the FA and some elevated instability is allowing for these embedded storms as well. CAMs are initializing and handling this activity poorly but this batch of convection will likely continue eastward into the Pee Dee region before dissipating near daybreak with morning lows in the upper 60s to near 70.

This front will slowly continue southward, likely stalling out somewhere in the central Midlands this afternoon as the axis of the upper trough swings overhead. Some scattered cumulus during the afternoon should give enough of a break in cloud cover to allow strong insolation to reach the area, allowing temperatures to raise into the upper 80s to near 90 in some spots as dewpoints remain near 70F. The stalled front and muggy conditions should allow for a more typical summer day with scattered diurnal convection developing where the greatest coverage is expected into the eastern Midlands with the sea breeze likely pushing in here as well. The severe threat is rather low with lacking shear, but soundings indicate good mixing should allow for moderate to high DCAPE values and thus isolated damaging wind gusts cannot be ruled out in any more robust updraft with heavy rainfall possible as PWATs remain near 1.7-1.8". This activity likely tapers off with the loss of heating during the evening before the area stays mostly dry into the overnight, though the front likely lingers in the area. Cloud cover due to remaining high moisture content should keep overnight lows mild once again, in the upper 60s to low 70s.

SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/

Key Message(s):

- Scattered afternoon convection each day.

Thursday and Thursday night: Upper ridge remains centered well south of the area. At the surface, a weak stationary front will be generally washing out and lifting northward through the day. Another period of afternoon and evening showers and thunderstorms should be on tap again across the region. Highs reaching back to around 90 degrees. Thursday night will see much of the convection dissipate, although isolated showers can not be ruled out during the overnight hours. Lows around 70 expected.

Friday and Friday night: Upper ridge will remain centered south of the area once again. Combination of Atlantic moisture, Gulf moisture, and some instability will keep afternoon convection potential across the area. Main driver of convection may be the inland moving sea-breeze during the afternoon, then maintained by convective outflows into the evening. Convection should be dissipated towards midnight across the area. Temperatures during the day rise into the upper 80s, while overnight lows fall into the lower 70s.

LONG TERM /SATURDAY THROUGH TUESDAY/

Key Message(s):

- Typical summertime pattern will continue with afternoon showers and thunderstorms

An upper level ridge will remain positioned over the western Atlantic, with the western periphery extending into the southeastern states. At the surface, moisture will remain high across the region. Convection each day driven by remnant outflow boundaries afternoon sea-breeze. Overall the severe threat remains low, however a strong thunderstorm cannot be ruled out. Both high and low temperatures will remain near normal through the period.

AVIATION /11Z WEDNESDAY THROUGH SUNDAY/

VFR conditions continue at most of the TAF sites with periods of MVFR being seen this morning before VFR conditions return by mid-morning and into the afternoon. Restrictions may be seen tonight and into Thursday morning.

VFR ceilings are continuing to prevail at the TAF sites, though satellite imagery has shown a stratus field across the eastern Midlands slowly reach near the sites where DNL had a period of IFR ceilings before quickly rebounding to VFR. Due to this, I expect brief periods of MVFR to possibly IFR ceilings will be possible before 13z to 14z, but these restrictions are looking to be fairly spotty and brief. Any possible restrictions move out by 14-15z with scattered cumulus development expected with 4-8 kt winds out of the southwest that become more southerly this evening. Diurnal showers/storms continue to be expected after 18-20z today but coverage still looks to be limited enough to not include mention at most of the TAF sites outside of a PROB30 group for OGB where coverage is expected to be slightly greater. This activity then wraps up into the evening with some SCT to BKN high clouds moving in overnight, though guidance is starting to again hint at possible ceiling restrictions tonight and into Thursday morning as a similar set up to the past couple nights is seen. Confidence is too low at this time to add restrictions at the end of this TAF period but this will continue to be monitored.

EXTENDED AVIATION OUTLOOK...Brief flight restrictions are possible each day with typical summertime thunderstorms throughout this week and into the weekend.

CAE WATCHES/WARNINGS/ADVISORIES

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