Tropical Storm Debbie certainly packed a punch on August 9-10 with rain totals ranging from 2-6” for the Shenandoah Valley. Lots of reports of flooded basements in the region as stormwater infrastructure struggled to keep up with the deluge.
This past Friday, I stated that the official NOAA river level forecast called for the South Fork to crest right at 12’ with a 26,000 CFS reading at the Front Royal gauge. She actually crested Saturday morning at 7.11’ and a 10,600 CFS reading. Impressive, but only about 40 percent of the expected flow. So why is that? Why didn’t the river hit the forecasted numbers?
(These charts represent (1) the prediction on August 8 stating it was going to climb to 12′; (2) shows the actual CFS (cubic feet per second) reading; and (3) the actual river height measured at the Front Royal gauge.)
Well, for starters, forecasting river levels is more art than science even though there are lots of modeling scenarios out there. How long will the heaviest portion of the storm cell linger over our area? Is it falling on areas that can handle the storm and have the rain water temporarily captured in stormwater detention ponds or is all of the rain going to immediately end up in streams and the river. How dry is the earth and how much rainwater can it hold onto?
The next question everyone has is whether the drought is over and are we out of the woods. Short-term a qualified yes. Long-term? Doubtful. It’s kind of like going to grandma’s house for Thanksgiving. You can stuff yourself with turkey, mashed potatoes, dressing, and that killer pecan pie. Can’t eat another bite. But yet, eight hours later you’ll be hungry. The river is kind of like that. On Saturday she was at 7.1’ and this Wednesday evening she will be back down under 2’ at the Front Royal gauge. So we are not out of the woods.
If you want to get out on the river this week, give Don Roberts and his crew at Front Royal Outdoors a shout and they can put you on some juicy water before the summer is over. Call them at 540-635-5440 or log onto Frontroyaloutdoors.com.
Be safe, have a great week, and don’t forget, Respect the Shenandoah!
