Harrisburg tornado described as EF-4; more severe weather possible Friday

Storm surveyers from the National Weather Service have initially pegged last night's tornado that hit Harrisburg, Illinois, as an EF-4, the second highest classification. Here is what their bulletin states:

PRELIMINARY INFORMATION ONLY...ASSESSMENT ONGOING

THE FOLLOWING IS AN INITIAL REPORT IN...FROM A DAMAGE ASSESSMENT ONGOING FOR THE CITY OF HARRISBURG IN SOUTHERN ILLINOIS.

* EVENT DATE - WEDNESDAY FEBRUARY 29 2012

* EVENT TIME - 456 AM CST

* EVENT TYPE - PRELIMINARY EF4 TORNADO

* EVENT LOCATION - SOUTHERN PART OF HARRISBURG

* PEAK WIND - ESTIMATED 170 MPH

* AVERAGE PATH WIDTH - ESTIMATED 200 YARDS

* DISCUSSION/DAMAGE - STRIP MALL NEAR WAL MART SUFFERED MAJOR DAMAGE. ADDITIONAL INFORMATION REGARDING DAMAGE...INJURIES AND FATALITIES WILL BE ADDED TO THIS PRELIMINARY REPORT...AS WILL PATH LENGTH. AS OF RIGHT NOW...THE LATEST IS 6 DEATHS HAVE BEEN REPORTED.

The storm surveys are focused on Illinois and Kentucky today. Missouri, of course, saw more than its fair share of damage. We'll know more in the coming days as the damage is assessed.

Meanwhile, another violent outbreak of thunderstorms is possible later this week. The Forecast Discussion from the Paducah NWS office warns:

SEVERE WEATHER IS POSSIBLE AGAIN LATE THURSDAY NIGHT AND ESPECIALLY ON FRIDAY. THE LATEST MODEL DATA SHOWS PARAMETERS SIMILAR TO WHAT WE SAW ACROSS THE REGION EARLY THIS MORNING. THE FORECAST IS SUBJECT TO CHANGE...AS NEWER DATA BECOMES AVAILABLE. SO AT THE VERY LEAST...STAY TUNED TO THE FORECAST OVER THE NEXT 48 HOURS FOR DETAILS.