DELMARVA - Heading into Saturday night, a zonal flow aloft sets up temporarily as the first upper trough begins to pull away. By Sunday, a new upper-level low will be centered north of us, with a shortwave approaching the region. On Monday, the upper trough axis will swing through the area.
At the surface, weak high pressure will start moving off the southeast coast on Saturday night, allowing a cold front to approach the region on Sunday. In the wake of this front, broad but expansive high pressure will begin to move in from the west as a secondary cold front passes through on Monday.
Saturday night looks to remain dry, except for a slight chance of a rain shower in the Poconos. Increasing clouds are expected with lows in the upper 50s to low 60s. PoPs (Probability of Precipitation) will increase from northwest to southeast during the day on Sunday as the initial front approaches. However, forcing is relatively weak, so not expecting much more than a 20-30% chance of showers and/or thunderstorms on Sunday. The best chance of precipitation will be north and west where better forcing is present. By Sunday night, skies will begin to clear and should remain at least partly cloudy on Monday.
At this point, Monday appears to remain dry as drier air is expected to be in place with the secondary frontal passage. Highs for Sunday and Monday will be in the 70s to low 80s.