Normally, this discussion would be a Premium discussion only, but I wanted to break down this forecast’s failure to answer important questions and show what Premium Consulting Members gain, especially as we move into the Fall and Winter months.
The forecast for Friday, July 12th, through the morning of Saturday, July 13th, was that a persistent upper-level trough and a stationary front would interact with a tropical disturbance moving around the western Atlantic ridge from the Carolina coast to the coastal waters of southern New England. This feature would produce strong lifting over the northern Mid-Atlantic, with the strongest lifting from the Delaware River to the coastal plain. With precipitable water values ranging from 1.75″ to 2.50″ over the region, the potential for tropical downpours producing rainfall amounts of 1.50″ at a minimum and some locations over 3″ was a reasonable threat to advertising.
The reason why this forecast idea did not pan out for most of the region outside of coastal southern New Jersey and southern Delaware was because the lifting features were slightly positioned further to the east than expected. All other factors were forecasted correctly, but the locations of the strongest lifting displaced the enhanced rainfall rates to the east, which translated to less rainfall for much of eastern Pennsylvania, central and northern New Jersey, southeastern New York, and Connecticut. Meanwhile, the excessive rainfall did develop in southeastern New Jersey and Delaware with rainfall amounts over 4″ in some locations.