Lead Forecaster Daniel Crawley
Good Friday morning to everyone, the stagnant weather pattern that we have experienced this week begins to change a little bit starting today.
The one constant is that we continue to have abundant tropical moisture across the Southeast US and it’s in no hurry to move out thanks in part to the Bermuda High currently located overhead.
The chance is with our trough over the northern tier of the country. It has allowed a frontal boundary to make its way into the Tennessee Valley. We mentioned earlier this week how the heavy rain focus would slowly shift southward and that has indeed happened.
As of this morning we have a conveyor belt of upper level winds and deep moisture running roughly in a line from Memphis to Chattanooga to Raleigh. It’s in this corridor where thunderstorm coverage is going to increase significantly over the next 48 hours.
For most of this week our storms have been more a process of differential heating off the high terrain. That starts to change today as the front itself will work in tandem with terrain effects. This will allow for more organization of storms and the ability for convective activity to extend beyond the typical hours of maximum heating.
Rainfall amounts this weekend look to be in the 1-3 inch range widespread across East Tennessee and Western North Carolina. It’s with individual thunderstorm complexes that will need to be monitored for amounts that could exceed the forecasted amounts.
Weather Prediction Center has placed the Foothills and Western Piedmont in a Marginal Risk for Excessive Rainfall with higher risks just to our west. These same risks also extend into the weekend with a current Day 3 Slight Risk for everyone.