... Dry high pressure will prevail through the weekend. A cold front is expected to move through our area on Monday and could produce some strong and possibly even severe thunderstorms. Another front will lift over our forecast area on Thursday and bring widespread precipitation to the region. Temperatures will remain above normal through Monday and then cool to below normal by late week.
NEAR TERM /THROUGH TONIGHT/... As of 1035 AM: The least vestiges of morning fog/low stratus are burning off across mountain and lake/river valleys late this morning, giving way to mostly sunny skies for the remainder of the day, albeit filtered through mostly thin cirrus. Insolation should be sufficient to allow temps to climb a few degrees above normal again this afternoon.
Over the next 24 hours, a progressive upper pattern will amplify with an upper low closing off and deepening over the upper Midwest and the resulting downstream ridge pushing sfc high pressure farther off the Mid-Atlantic coast. Nevertheless, the sfc high will continue to ridge back and keep our weather quiet for one more day. A lead short wave is shown to lift northeast from the MS Delta region late in the day and over the fcst area tonight, but this feature will be so moisture-starved that even cloudiness might be difficult to develop. Instead, the western Carolinas will remain in-between the front approaching from the west and a sfc low developing off the coast. Precip associated with both systems will probably remain outside our fcst area through daybreak Monday.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... As of 315 AM EDT Sunday: The short-term fcst picks up at 12z on Monday with an embedded upper trof approaching our area from the northwest early Monday. The trof axis is expected to pass just to our north late Monday into early Tuesday and then move off the Atlantic Coast late Tuesday into early Wednesday. As it does so, most of the model guidance has the trof morph into a large, closed h5 low and linger just off the coast. At the surface, a moist, SLY return flow will be over the Southeast as the next frontal system approaches the Carolinas from the west. The front is expected to push thru the fcst area late Monday and should be moving east of our CWA by early Tuesday. In its wake, broad Canadian high pressure will spread over the region from the NW and dry things out for the remainder of the period. The latest model guidance still has the front moving thru the forecast area at a pretty good clip, so we still aren't expecting any excessive QPF at this point. The latest Day 2 Convective Outlook from SPC is very similar to the previous Day 3 Outlook and still has our entire CWA under a Slight Risk. They appear to still be favoring a NAM-type solution that generates impressive low-lvl shear/helicity and decent instability, especially over our Piedmont zones. The latest runs of the HREF also suggest that some mini-supercell type thunderstorms could develop east of our higher terrain, but it develops the strongest cells just east of our CWA and more over Raleigh's fcst area. At this point, the Slight Risk still appears warranted (although probably not across the higher terrain). Otherwise, temps will start out well-above normal on Monday and cool to near-normal by Tuesday.
LONG TERM /WEDNESDAY THROUGH SATURDAY/... As of 245 AM EDT Sunday: The extended forecast picks up at 12z on Wednesday with a large, closed upper low lifting off the Atlantic Coast as upper ridging begins to spread back over the Southeast in its wake. The upper ridge won't hang around for very long, as very broad, southern stream upper trofing amplifies to our west and pushes the ridge offshore. As the trof approaches our area on Thursday, it will likely morph into a closed upper low and linger over the Eastern CONUS thru the rest of the period. At the sfc, high pressure (centered well to our north) will be over the region as the period begins. The high will not hang around for very long, as another low rapidly deepens over the Southern Plains and lifts a warm front up and over the fcst area early Thurs. Beyond this point, it's still not very clear exactly how long the above-mentioned low will linger over our region and keep precip chances around. The ECMWF remains more progressive with the system and lifts it NE and away from our area on Sat, with broad high pressure spreading back over the Southeast to end the period. The GFS however, keeps the low centered to our north into Sunday and is slower to dry our area out. Thus, I kept a solid chance PoP over most of the CWA thru Saturday. I also increased the coverage and amounts of QPF for the latter half of the period. Temperatures are expected to start out near normal on Wednesday and cool to well-below normal by Friday.