Revisiting the Historic November 17, 2013 Tornado Outbreak

Fast Facts:

• This outbreak produced 75 tornadoes across seven states.  32 of these tornadoes were at least EF-2 strength, the most to occur in a single event since April 27-28, 2011.
• Eight fatalities were reported, all in Illinois.  This was Illinois' deadliest tornado outbreak since February 29, 2012.
• 25 of the tornadoes occurred in Illinois, the 4th largest outbreak in the state since reliable records began in 1950.
• There were two EF-4 and three EF-3 tornadoes in the state.  Of the 25 overall tornadoes, 14 were at least EF-2 strength, 2nd most in any event since 1950.
• The tornado which moved through Washington, an EF-4 with maximum winds of 190 mph, was the strongest November tornado on record in the state. Debris from this tornado was found as far away as Chicago.
• Property damage from the tornadoes statewide was estimated around $1.05 BILLION.  Of this, over $800 million damage occurred in Washington alone.

The Event:

The above map is of locations where tornado damage occurred based on NWS storm surveys.  Note that each report does not reflect a different tornado, with many reports clustered together or strung out in a path being caused from the same tornado.

A powerful low pressure system tracked from the central Rockies toward the southern Great Lakes on November 17th. As the system approached central Illinois, unseasonably warm and humid air was pulled northward into the area, resulting in high temperatures soaring into the 70s. This very unstable air mass, coupled with strong jet stream level winds aloft, created numerous strong to severe thunderstorms. Many of the storms became supercells, producing damaging long-track tornadoes.

The event produced a total of 25 tornadoes across the state.  Click on the links for more detailed information.

 * - Total track was 42 miles, 31 of which were in Kentucky.

	Left:  Anthony Khoury took this picture of the Washington tornado. Above:  Radar imagery of the Washington area corresponding to the time of the picture.  The white and pink radar echoes are caused by airborne debris reflecting off the radar beam. Right:  An update to the Tornado Warning issued a few minutes before the tornado struck Washington.
Damage pictures from Washington:

The tornado which went through Gifford, in Champaign County, tracked for nearly 30 miles, crossing northwest Vermilion and far southern Iroquois Counties. Jessie Starkey photographed the storm when it was near Gifford. The radar image displayed here, taken at about the same time as Jessie's photo, shows the motions within the storm. A strong circulation is shown where the bright green and bright red colors come together.

		These Google Earth satellite images of Washington were taken 6 months apart. The one at left was taken the day after the tornado, and the one at right was taken in April 2014. The scar on the landscape was still clearly visible several months later.
		A close-up look of the Washington track in Google Earth (left image) showed swirls in the dirt, clearly seen in the barren farm fields. This was seen across most of the track through Woodford County and even into LaSalle and Livingston Counties. At right, in this picture taken by the Illinois Emergency Management Agency, the swirls in the dirt are seen along the Gifford tornado track.

Why So Few Deaths?

In the days following the storm, the one question we kept getting asked, over and over, from media outlets across the country (and outside the country; we actually did an interview with a radio station in Japan!), was this:

With so much destruction, why were the numbers of fatalities and injuries lower than other recent, but similarly strong, tornado events across the country?

We will never know all the reasons, but there was a rather consistent theme:

• The potential for a high impact severe weather event was talked about days ahead of time. Many people were prepared.
• It was a Sunday morning and early afternoon. Many people were in church, out for brunch, or shopping for the upcoming holiday season, so they were not home when the storms struck residential areas.
• Many people had basements or storm shelters to go to during the storm. This was EXTREMELY important considering the strength of these tornadoes.
• We have more ways than ever before to warn people. There were numerous stories about people being warned on television, radio, weather alert radios, cell phone messages (also known as Wireless Emergency Alerts – WEA), social media sites like Facebook and Twitter, and outdoor warning sirens.

How Well Was This Forecast?

Outlooks for Sunday, November 17  issued from the Storm Prediction Center.  Top row (L-R): Forecasts issued on Wednesday, Thursday, and Friday.  Bottom row (L-R): Forecasts issued Saturday and Sunday, and a mapping of the received reports.

Outlooks from the Storm Prediction Center (SPC), which were incorporated into our Hazardous Weather Outlooks, indicated as early as Thursday, November 14th that an outbreak of severe storms with tornadoes was possible the following Sunday. The SPC severe weather outlook issued on Saturday indicated a Moderate Risk of severe weather the next day, meaning widespread severe storms were expected with potential for high winds, large hail, and tornadoes.  Our Hazardous Weather Outlook issued on Saturday stated:  The latest indications suggest storms will develop in the Illinois River Valley around 10 am, then push east of I-55 after 1 pm.  Damaging wind gusts in excess of 70 mph and isolated tornadoes will be the primary threats. The SPC severe weather outlook issued very early Sunday morning indicated there was a High Risk of severe weather in eastern Illinois.  The updated outlook at 7 am extended this risk as far west as the Illinois River.  A "High Risk" indicates that a major tornado outbreak is expected.  The outlook mentioned "The greatest, most concentrated severe threat, including potentially strong and/or long-track tornadoes, should focus over the Ohio Valley and adjacent parts of the Midwest beginning later this morning."

Learning More:

For more information about this outbreak in Illinois, the NWS offices that cover the area have set up special web pages. They contain more detailed information on the exact tracks of each system, radar imagery, and more.

• NWS Lincoln: Central and southeast Illinois (includes the Washington and Gifford tornadoes)
• NWS Chicago: Northeast Illinois
• NWS St. Louis: Southwest Illinois (includes the New Minden tornado)
• NWS Paducah: Far southern Illinois

Several YouTube videos are available of the tornadoes and aftermath. Search for "Washington Tornado 2013" and "Gifford Tornado 2013".