... A front moving into the region will support showers and thunderstorms again today with a gradual decrease in activity this weekend as drier air filters into the region. Increasing easterly flow off of the Atlantic Ocean may bring a return to shower activity and cooler conditions sometime early next week.
NEAR TERM /THROUGH TONIGHT/... As of 650 AM EDT: Showers continue to dissipate as they move across the mountains early this morning. Widespread low clouds and patchy fog will be in place to start the day as well.
Patchy fog will end quickly after daybreak, but low clouds will only slowly lift through the morning. Low clouds may scatter out by early afternoon outside of the mountains, but will return through the day. A short wave crosses the area today along with the right entrance region of an upper jet streak. A weak surface low and trof associated with these features will cross the area today as well. These will combine to bring a likely chance of convection to the area today. Expect convection to move in or develop across the mountains by late morning then move ESE across the area through the day. Despite the clouds, copious low level moisture will help instability reach moderate levels. The short wave will help moderate shear to develop, mainly across NC. dCAPE values won't be especially high, but a few severe storms will be possible, especially across the NC foothills and piedmont where organization may develop closer to the short wave and surface trof. Highs will range from near to a couple of degrees above normal.
Convection will diminish during the evening and end overnight with the loss of heating and the short wave and surface trof moving east of the area. Expect at least patchy fog development overnight with dense fog possible but still uncertain. Lows will be around 5 degrees above normal.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... As of 330 am EDT Friday: A sharpening trough over the Great Lakes will press east off the New England Coast by Sunday night. Around the same time Cristobal should be poised to make landfall along the Central Gulf of Mexico. The trough will be the main player for our area in the short term as it maintains dry northerly flow atop the region, while maintaining a keeping a surface boundary at bay to southern areas in spite of Cristobal's gradual increasing influence atop the region. Isolated showers and thunderstorms are expected to develop, mainly across the Upstate of South Carolina into the mountains of North Carolina where somewhat better moisture and instability reside. Steep low level lapse rates and dry air aloft would support a damaging wind threat should stronger thunderstorms develop. Increased subsidence aloft, dry northwest flow aloft and high clouds associated with Cristobal possibly building into southern areas Sunday will limit shower activity to the southwest mountains. Seasonably highs in the 80s to 90 are expected each day with equally warm lows in the 60s to near 70.
LONG TERM /MONDAY THROUGH THURSDAY/... As of 345 am EDT Friday: An impressive 590 dm ridge should build nearly overhead early next weak, with associated sinking motion limiting thunderstorm activity if not shower activity altogether. Typically this would be a hot pattern, but there's some potential for the aforementioned boundary to amplify between surface high pressure offshore and the remnants of Cristobal as it pushes inland. This could deliver a steady easterly fetch of low level moisture and clouds off of the Atlantic. The forecast has been trended this direction with clouds and shower chances increasing for southwestern areas by Tuesday. However, temperatures in particular are probably over done if we get locked into this moist pattern. Fortunately model guidance continues to absorb what is left of Cristobal into an amplifying trough across the Upper Midwest into the Great Lakes, effectively deflecting the heaviest rain and greatest excessive rainfall threat well to our north. Left over energy and surface boundary may support an enhanced diurnally driven set up for convection late in the work week. Above normal temperatures Monday should gradually fall to near or below normal later in the week due to increased cloud cover, possibly followed by a cooler airmass.