Flash Flood in Spencer County, Kentucky

Multiple water rescues occurred across Spencer County.

During the overnight hours and into the morning on January 3rd, a strong system moved across central Kentucky, bringing isolated damaging wind gusts and widespread heavy rainfall. The system was associated with a negatively-tilted upper-level trough which moved from the Four Corners region on January 2nd to the upper Midwest by January 4th. A surface cyclone transited in a similar fashion to the upper trough, with a surface warm front developing across central Indiana during the evening hours of January 2nd. This setup positioned central Kentucky in the broad warm sector of the cyclone, allowing for ample low-level temperature and moisture advection. As a result, precipitable water approached all-time maximum values for early January, and temperatures overnight January 3rd were unseasonably warm in the low-to-mid 60s. This provided a modest amount of instability, with between 200-500 J/kg MUCAPE across southern Kentucky. With a 65 knot 850 mb jet overhead, strong vertical wind shear was present, and this shear combined with the modest amounts of instability to promote the development of widespread showers and thunderstorms. While a couple storms were strong enough to produce isolated damaging wind gusts, overall SBCAPE was limited, preventing more widespread severe weather. On the other hand, the steady stream of moisture allowed for training convection which created widespread areas of heavy rainfall, with many areas receiving over 2 inches of rain. Where the heaviest rain fell, flash flooding occurred, leading to many road closures and several water rescues across the area.