Small, short-lived tornado known as a "landspout" touches down around 2:59 p.m. Thursday in Plainfield
A small tornado touched down over the Lakewood Nursing Center in central Plainfield Thursday afternoon and continued north into Bolingbrook near 127th and Essington before retreating into the clouds only minutes later. The touchdown occurred at 2:59 p.m. Jeremy Hylka, reporter for WJOL radio, accompanied Jim Allsopp of the NWS-Chicago Forecast Office as he led a survey team to investigate storm damage. Jeremy tells us that the survey team’s Initial findings indicate Thursday’s twister was an unconventional tornado—an especially small, short lived twister which storm chasers have dubbed “landspout”.
A microburst was ruled out as the cause of Thursday’s damage—a conclusion supported by a video of the storm shot by the Plainfield Fire Protection District. Microbursts demand a layer of dry air in the mid levels of the atmosphere in order to form. Atmospheric measurements Thursday indicated such a dry layer didn't exist—that the atmosphere above NE Illinois was saturated with moisture and unlikely to foster microbursts.
Damage from Thursday’s storm was fairly minor. The twister’s winds removed a small portion of the Lakewood Nursing Home's roof. Several cars were reportedly flipped by the storm and lawn furniture and a trampoline was tossed about by the small twister's winds.
Doppler radar scanned the storm cloud tops at up to 35,000 ft. at the time it reached Plainfield. A more damaging tornado is reported to have touched down some time later (around 4:40 p.m.) farther east in LaPorte County, Indiana, where there were injuries.
The dramatic shots you see here are of another storm sweeping across NE Illinois about the same time Thursday’s twister touched down. They depict a wall cloud-like cloud mass beneath the base of a thunderstorm as viewed from Rockdale, Illinois—just south of Plainfield. The photographer was Jennifer Scamardi. A “wall cloud” is an isolated lowering of the cloud base which marks the region of t-storm's strongest updrafts and is a feature beneath which a tornado vortex often "spins up". Fortunately that didn’t happen in this case. Many thanks to Jennifer Scamardi for sharing these remarkable shots with us.
--Tom Skilling
WGN-TV Chief Meteorologist