Hydrologic Vulnerability Assessment – Southeast U.S.
Despite recent rainfall, the current hydrologic vulnerability remains low for the upcoming peak of tropical season.
Recent Rainfall/ Soil Moisture
Rainfall has been “holding its own” during the month of July. For much of the area, rainfall has averaged close to, or even a bit above, normal since the early part of July. In the “Past 14-Day Percent of Normal Rainfall” image, the areas in blue represent above-normal rainfall. However it is more important to review a longer-term rainfall analysis. If we look at the “Past 30-Day Percent of Normal Rainfall” image we see that most of the Southeast remains dry. While rainfall has picked up recently, longer-term, drought is the prevailing regime.
Soil Moisture Vulnerability: Low
Stream flow has been persistently low, for many months, over the region. Many rivers within the core of drought are at historic low levels. It would take as much as 5 inches of rain to bring (most) rivers close to bank full.
Stream Flow Vulnerability: Low
Most reservoirs remain well-below-normal and can “hold” several inches of runoff before needing to release water downstream.
Reservoir Capacity Vulnerability: Low
There are no signs of tropical storm development that would impact the Southeast U.S. during the period July 22 – 31.