Monitoring Tsunami Impacts Across the Pacific; Air Quality Concerns; Dangerous Heat; Critical Fire Weather for the West

Tsunami impacts continue for portions of the Pacific basin. Wildfire smoke causes unhealthy air in Midwest to Great Lakes. Heat dome spans Mississippi Valley to Mid-Atlantic with excessive heat warnings and advisories. Critical fire weather in Great Basin to Pacific Northwest (dry thunderstorms). Cold front spawns severe storms/heavy rain in Central U.S. today, shifts to East Coast Thursday. Read More >

February 20-21, 2014
Severe Weather, Tornadoes, and Flooding

A quasi-linear convective system (QLCS) developed ahead of a rapidly deepening low pressure system moving across the mid-west. This line produced sporadic damaging winds as it crossed the Wilmington, OH forecast area. Bowing and broken-s radar signatures appeared along the line of convection which became the focus of 3 tornado spin-ups as well as small scale enhanced straight line wind damage.

A discrete cell developed just ahead of the main line of convection in southeastern Indiana. This cell began to rotate aloft with this rotation quickly translating to the surface in just a few minutes. An EF1 tornado touched down in Ripley, County Indiana as a result of this circulation. The cell then got absorbed by the pursuing line of convection.
A broken-s signature developed as the line entered west central Ohio. This segment eventually produced an EF-0 tornado in Montgomery County
The QLCS began to weaken as it moved into a more stable airmass across central Ohio during the middle of the night. However, wind shear was still very strong, and was sufficient to bring a weak circulation briefly to the surface in Delaware County in the form of an EF0 tornado.
Snow melt that had been occurring leading up to the event had already produced areas of standing water over frozen ground. Rain from this system added to the runoff from the melted snow, resulting in minor flooding across the area.