Sugar Mountain

Summary

SYNOPSIS

... Dry and warm high pressure moves off the Carolina coast as a front approaches from the west then stalls over our region for the weekend. This front will result in periodic thunderstorms and showers starting Friday and remaining through the weekend. A general summertime pattern sets up early next week, which will likely support scattered thunderstorm development each afternoon.

NEAR TERM /THROUGH FRIDAY/... As of 237 PM EDT Thursday: A few small fair weather stratocu have developed across the region this afternoon. Temp/dewpt trends look good. What a nice day, courtesy of an upper ridge on the East Coast supporting sfc high pressure to our east. No changes.

The upper ridge to our east will move slowly offshore tonight, allowing moisture to move back in from the south/southwest toward morning. A lead short wave lifting out of the trof well to our west will move over the mtns after midnight, but minimal response is expected through sunrise as forcing remains weak with this feature. Clouds will increase, however, which will help to keep min temps relatively mild. Friday looks to be a trend toward a more active stretch of weather. With the upper ridge offshore, we end up in a deep SW flow aloft that has several embedded short waves, the first of which will linger across the region through peak heating. The situation appears relatively benign, with precip probs slowly ramping up from the west with likely over the mtns and chances east of the mtns. We may get up to 1000-1500 J/kg of sfc-based CAPE to work with in the afternoon, which will give us the environment to support a few thunderstorms, but for now the severe storm risk appears to be low. High temps should be on the order of 5-10 degrees above normal.

SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... As of 215 PM Thursday: A ridge of high pressure slides off the east coast as an unsettled pattern sets up for the weekend. By the start of the period on Friday night, a series of shortwaves traverses toward the CWA. A well saturated profile is expected to enhance rainfall chances by Saturday and into Sunday. However, the area will be in a weak flow regime and any upper air support would be minimal. Little if any DPVA appears in the GFS as the 500mb gradient remains broad. This will limit the amount of thunderstorms that could occur, along with minimal instability. At this time, a small amount of muCAPE exists during the day on Saturday, which could be enough for some lightning strikes and thunder. Strong storms could occur, but confidence for the potential for severe weather is low. This could change as Saturday gets closer and will continue to monitor closely. Despite widespread showers expected. The QPF response is not impressive with the Storm totals struggling to reach 1 inch between Friday night and Sunday morning, with the somewhat higher amounts east of the mountains. Temperatures on Saturday will be a tick or two cooler than the past few days with most of the area reaching the upper 70s. By Sunday, showers continue and start to taper off by the end of the period, but at least chance PoP remains for Sunday. Winds are expected to remain relatively light with low end gusts possible in the eastern NC Piedmont on Sunday.

LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... As of 220 PM Thursday: The general pattern remains similar at the beginning of the extended period with a broad flow aloft and shortwaves moving through. Meanwhile, out west, a trough begins to develop and swing towards the central CONUS. Another, less impressive shortwave over the central plains moves into the NE, sending a ripple downstream toward the CWA. Guidance does keep a deep layer of moisture remaining across the southeast, meaning PoPs will remain elevated Monday before tapering off Monday night. By Tuesday, a strong upper low swings northward over the Dakotas and guidance from the EURO and GFS have a boundary extending toward the CWA. The better forcing remains to the NW and far out of the CWA, but this could change. Too much uncertainty exists with this system, but showers and rainfall look to occur. This makes for yet another unsettled pattern, but nothing that looks concerning in the way of any severe weather at this point. High pressure could start to creep back in toward the end of the period or mid-week, kicking up daytime temps into the first 90s of the season.