Some showers have developed over the southern sections of ENC through the combination of the frontal system to the south and daytime heating. These will persist into this evening as the front to the south begins to return northward as a warm front.
An upper level trough currently over the Great Lakes Region will continue to track southeastward with an associated surface low over Ohio traveling northeastward through tonight. An increase in southwesterly flow will be the driving force of the warm front forecast to travel northward overnight and into Tuesday.
The upper trough continues to dig southeastward during the day Tuesday as the leading cold front begins to approach the region. Ahead of the front instability will be in place for some scattered thunderstorms to develop mainly over the northern sections adjacent to the warm front lifting northward.
The cold front will begin to move through ENC late Tuesday night and into early Wednesday morning. The models favor a line of showers and potential storms moving from the northwest just ahead of the front. This will be occurring after during the early morning hours which leads me to believe that the atmosphere ahead of the line will be relatively weak and I don’t expect severe weather associated with this passage.
The front will be slow to move offshore leaving the potential for daytime storm development ahead of the front during Wednesday. This activity, if it does develop, will be to the east of Highway 17 and along the coast. These storms will probably not reach severe criteria but careful attention is needed as some strong thunderstorms could develop. This passage will will do little to reduce high temperatures across the area as most areas will see highs reach the upper 80s and potentially 90+. A secondary cold front will approach the region Thursday bringing in much drier air and cooler temperatures than normal for August. Highs for Thursday and Friday will reach only in the mid 80s with some higher temps far southwest but should remain well less than 90.