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 >

August 4-5, 2010
Several Rounds of Severe Thunderstorms

An extremely unstable airmass developed on the afternoon of August 4, with temperatures in the low to mid 90s and dewpoints in the mid to upper 70s. This airmass set the stage for very strong thunderstorms during the afternoon which produced widespread wind damage across western and central Ohio. The worst damage occurred across northwest Licking County where a large barn collapsed, resulting in two fatalities, and in Auglaize County where significant damage occurred to several structures.

A second round of severe thunderstorms swept through Indiana and Ohio during the evening hours of August 4. This resulted in several reports of wind damage across eastern Indiana, the Miami Valley and parts of central Ohio.

The thunderstorms that developed on August 4 left a boundary near the Ohio River overnight. This boundary served as a focus for a third round of thunderstorms on August 5. These thunderstorms affected areas near the Ohio river with damaging winds, including widespread tree damage in Mason County, Kentucky.