| April 2015 | Tornado (EF3) | Fairdale | 2 killed, 11 hurt, $8,000,000 | This is the third segment of the Rochelle-Fairdale EF-4 tornado. At its strongest, peak winds were estimated to be 200 mph. The tornado entered the county just southwest of Fairdale before directly hitting the small community. Peak winds were estimated at 165 mph in Dekalb County, rating this section of the tornado a high end EF-3. Approximately 71 homes in the community had been damaged, 17 of which had been completely destroyed with all walls collapsed or removed from the buildings. Some homes that were only nailed to the foundation were swept clean. Two fatalities and 11 injuries occurred in Fairdale. A 67-year-old woman and her neighbor, a 69-year-old woman, were both killed in their homes. The tornado began to shift north (left) at this point during its lifecycle as it left Fairdale. Several homes were heavily damaged with large sections of the roofs removed along Wheeler road and dozens of trees were snapped and uprooted. A few trees were debarked. The second story was ripped off of a home near the intersection of McNeal Road and Irene Road. A two-story rebar reinforced cinder block silo was destroyed. The tornado continued into Boone County just east of Irene Road. (Tornado 2c of 7). |
| August 1998 | Thunderstorm Wind | Kirkland | 12 hurt | no account filed |
| September 2008 | Flood | New Lebanon | 3 hurt, $15,000 | Flooding continued across parts of southern and central DeKalb County into the morning of September 14th. A car drove into flood waters on Rimsnider Road near Hinckley during the evening of September 13th. The car was swept away by fast flowing flood waters. A man, woman and small child (along with their pets) in the car, were able to get out of the car but were trapped on a small piece of land by water. Several hours later, they were rescued. |
| July 2003 | Thunderstorm Wind | Sandwich | 2 hurt | no account filed |
| June 1975 | Tornado (F2) | not stated | 1 hurt, $250,000 | no account filed |
| June 2007 | Thunderstorm Wind | Sandwich | 1 hurt, $10,000 | Vehicles damaged by blown over shelters, one minor injury. |
| April 1997 | Thunderstorm Wind | Sycamore | 1 hurt | no account filed |
| September 2008 | Flash Flood | Fairdale | $3,000,000 | Flash flooding or significant flooding was reported across much of DeKalb County, including street closures due to flooding, basement flooding and creek, stream and river flooding. Extensive flooding was reported in the Evergreen mobile home park near Sycamore. Street flooding was reported in Waterman, Hinckley and Shabbona. |
| August 2007 | Flood | De Kalb | $1,000,000 | After flash flooding from heavy rainfall on the evening of August 23rd, significant flooding continued across parts of central DeKalb County as rivers and streams overflowed their banks and flood waters took days to subside. During the morning of August 24th, Route 30 and 1st Street were impassable. A mobile home park was evacuated due to flood waters and Highway 64 was flooded with two feet of standing water. Flood waters inundated the Northern Illinois University campus and surrounding areas. Levees on campus were overtopped as water levels rose. Students from NIU helped sandbag in an attempt to hold back floodwaters. Roads and streets were closed due to flooding throughout DeKalb county and most schools were closed on the following Friday. Rescue workers evacuated residents from the Evergreen Village Mobile home Park on the east side of Sycamore as floodwaters inundated the entire area. Further downstream large areas flooded along the Kishwaukee River in the New Milford area. Campgrounds were inundated as well as streets and secondary roads. During the morning of August 24, Bethany Road was the only road crossing over the Kishwaukee River that was open to traffic. All other east-west road crossings had been closed. In total some 400 to 600 residents were displaced due to the flooding of the Kishwaukee River. The South Branch Kishwaukee River at DeKalb crested at 15.34 feet, the second highest crest on record. Storm total rainfall amounts included 4.85 inches in DeKalb, 3.50 inches in Waterman and 2.62 inches in Genoa. |
| July 2007 | Flash Flood | De Kalb | $750,000 | Torrential rainfall led to flash flooding in parts of DeKalb. Numerous roads were closed with four feet of standing water. Several people had to be rescued from cars in high water. Numerous basements were flooded and a retail store on Sycamore Street was flooded. A dorm on the Northern Illinois University Campus was evacuated. Rainfall amounts ranged from 3 to 5 inches across DeKalb. The highest amount was 5.00 inches at 13th and Scyamore Street, before the gage overflowed. |
| May 2014 | Thunderstorm Wind | Malta | $500,000 | An approximately seven mile swath of damage occurred on the south side of Dekalb which was consistent with 60 mph to occasionally 100 mph winds. Damage began near the intersection of Malta Road and Nelson Road and concluded near Lynch Road just south of Gurler Road. A warehouse on Harvestore Drive had a portion of the roof torn off along with a broken window. Some mobile homes in the parking lot were rolled or overturned. |
| August 2007 | Flash Flood | De Kalb | $500,000 | Kishwaukee River flooding houses and apartments. |
| August 2007 | Flash Flood | De Kalb | $500,000 | Extensive flooding of buildings at the Northern Illinois Univeristy campus. |
| September 2006 | Thunderstorm Wind | Waterman | $200,000 | Six, 75 foot tall power transmission poles were blown down and several trees were also blown down. Corn fields were flattened by wind. |
| July 2010 | Flash Flood | New Lebanon | $100,000 | Very heavy rain fell across north central De Kalb County during the early morning hours of July 24th producing widespread flooding and flash flooding. Street and basement flooding was reported. A trailer park in Sycamore was evacuated with almost 8 inches of rainfall reported in Sycamore. Many roads were flooded and closed in Sycamore. Route 72 was flooded in Kirkland. Storm total rainfall of 5.46 inches was measured two miles southwest of Genoa. |
| June 2010 | Thunderstorm Wind | De Kalb | $100,000 | A tree was blown down near Peace Road and Fairview Drive. Trees were blown down on multiple houses near 4th Street and Route 23. A large section of a roof was blown off of a house near 4th Street and Route 23. A 20 by 40 foot tent was blown down on the NIU campus. Tree limbs and power lines were blown down in many areas. |
| June 2008 | Thunderstorm Wind | Fairdale | $100,000 | The roof of a one story house was completely blown off and the east wall of the house was also blown down on Irene Road, about 2 miles south of Route 72. Trees were also blown down. |
| May 2014 | Thunderstorm Wind | De Kalb | $50,000 | A roof was partially torn off the oasis on I-88. |
| June 2013 | Thunderstorm Wind | Shabbona | $50,000 | Boats were tossed onto other boats at Shabbona Lake State Park. Large trees were snapped at the trunk or uprooted. Power poles were down near the state park office. |
| November 2013 | Thunderstorm Wind | Hart | $50,000 | Two older trees were blown down on the north side of the Oak Club of Genoa Golf Course and many trees were uprooted. In Genoa, house siding was damaged by the winds. A 100 year old oak tree cracked at the base and landed on a neighbors garage. |
| July 2008 | Thunderstorm Wind | De Kalb | $50,000 | A thunderstorm produced significant wind damage on the Northern Illinois University Campus with a peak wind gust of 69 mph. Trees and tree limbs were blown down. Several buildings sustained roof damage. A trailer was overturned on the west side of the campus. Tree limbs were also blown down across other parts of DeKalb. |
| August 2008 | Thunderstorm Wind | Sandwich | $40,000 | Three to six inch diameter tree limbs were blown down with numerous power lines blown down on Route 34 between Davis and Main Streets. A restaurant lost part of its roof. Storefront windows in downtown Sandwich were shattered. A car was damaged by a large tree limb. |
| April 2010 | Thunderstorm Wind | Malta | $25,000 | A barn was destroyed. |
| June 1977 | Tornado | not stated | $25,000 | no account filed |
| April 1967 | Tornado (F1) | not stated | $25,000 | no account filed |
| July 1959 | Tornado (F1) | not stated | $25,000 | no account filed |
| August 2018 | Lightning | Sandwich | $20,000 | A house near the intersection of Fourth and DeKalb Streets was struck by lightning. The house's tower burst apart, exposing the third floor attic and other elements. Pieces of the roof, glass windows and electric outlets were blown across the street. Everyone in the home escaped with no injuries reported. |
| June 2013 | Tornado (EF1) | Shabbona | $20,000 | A National Weather Service storm survey determined an EF-1 tornado with maximum winds around 95 mph occurred near Shabbona. The maximum damage occurred along approximately a mile long path where the tornado snapped numerous utility poles and around 80 percent of the large hardwood trees. Along the remainder of the path there was minor tree damage and minor shingle peeling, but for the most part the tornado did not intersect any structures. |
| June 2013 | Thunderstorm Wind | Sandwich | $20,000 | Sandwich Police reported numerous trees and power lines blown down. One tree fell on a vehicle, but the occupant was not harmed. |
| July 2011 | Thunderstorm Wind | Waterman | $15,000 | Winds estimated to 70 mph caused several trees to snap. One large oak tree fell onto a house and car, but damage to property was minimal. The press box at DeKalb High School was blown over. The building was secured by pilings set in concrete, which were pulled out of the ground. Power lines were downed near Normal Road and 10th Street. A tree limb fell onto a home and damaged the gas meter. Portions of a corn field were flattened in Waterman. |
| March 2007 | Thunderstorm Wind | De Kalb | $15,000 | At South Pointe off Gurler Road, a large portion of a roof was blown off including the roof liner, insulation and roofing. Two trees were blown down onto Gurler Road. |
| June 2013 | Thunderstorm Wind | Rollo | $10,000 | A large grain bin was dented by strong winds. Multiple large trees were blown down. |
| May 2011 | Lightning | Sandwich | $10,000 | A house on 3rd street in Sandwich was struck by lightning. |
| June 2008 | Thunderstorm Wind | Malta | $10,000 | A semi truck was blown over near mile marker 86 on Interstate 88. |
| June 2008 | Thunderstorm Wind | Kirkland | $10,000 | Numerous trees, tree limbs and power lines were blown down in Kirkland. A construction trailer was overturned near Route 72 and Malta Road. |
| August 2008 | Thunderstorm Wind | Sycamore | $10,000 | Three utility poles were snapped off at their base. A large steel flagpole was bent over. Multiple trees and power lines were blown down. |
| March 2007 | Thunderstorm Wind | De Kalb | $10,000 | A large tree was blown down at Route 23 and Lucerne Lane, two blocks north of Interstate 88. Several branches were blown down from this location north to Route 38. A tree was blown down at Route 23 and Hillcrest. At Hopkins Park on Royal Drive, 19 trees were blown down along with numerous large limbs. In a wooded area south of the Park, another 9 trees were blown down. Across from Hopkins Park, a utility pole was blown down at Route 23 across from Hopkins Park. Two pine trees across from Ranger Road were snapped. Trees were blown down in Greenwood Acres just southwest of Route 23 and Bethany Road. A building under construction collapsed at Route 23 and Mercantile Road in Sycamore. |
| September 2006 | Thunderstorm Wind | Waterman | $10,000 | A tree was blown down onto a car. Numerous tree limbs also blown down. |
| June 2017 | Thunderstorm Wind | Hinckley | $5,000 | Several utility poles and power lines were blown down along East Chicago Road. |
| April 2015 | Tornado (EF1) | Fairdale | $5,000 | This tornado was identified from a storm chaser video and survey. Heavy damage to two small outbuildings occurred on Paulson Road. Maximum winds speeds were estimated to be 110 mph. The tornado continued into Boone County. (Tornado 4a of 7). |
| June 2013 | Thunderstorm Wind | Wilkinson | $5,000 | Winds were estimated to 60 mph near Bethany Road and 1st Street. Small newly planted trees were blown down. Powerlines were also blown down in the city of DeKalb. |
| July 2012 | Thunderstorm Wind | Wilkinson | $5,000 | A corn silo collapsed three miles north of Route 64 and 1st Street. |
| July 2012 | Thunderstorm Wind | De Kalb | $5,000 | Numerous trees, tree limbs and power lines were blown down from the north side of Dekalb southeast to the Dekalb airport. |
| June 2010 | Thunderstorm Wind | De Kalb | $5,000 | Trees, tree limbs, and power lines were blown down in many areas of De Kalb, with wind gusts estimated as high as 70 mph. Gutter damage was reported on a house on the northwest side of De Kalb. |
| August 2008 | Thunderstorm Wind | Sandwich Arpt | $5,000 | An airplane was flipped over at the Sandwich Airport. |
| August 2007 | Thunderstorm Wind | De Kalb | $5,000 | Utility poles blown down on Normal Street. |
| August 2008 | Thunderstorm Wind | Sandwich | $4,000 | Four utility poles and ten spans of electrical wire were blown down at the Sandwich Fairgrounds. Several trees suffered minor damage and three large oak trees were blown down. |
| August 2008 | Thunderstorm Wind | De Kalb | $3,000 | A large tree was blown down into a parking lot at the corner of South Fourth Street and Grove Street. Another tree was blown down blocking 10th Street just south of East Lincoln Highway. Numerous tree limbs and power lines were also blown down. |
| June 2017 | Thunderstorm Wind | Sandwich | $2,000 | Many power lines were blown down along with tree damage reported. |
| June 2013 | Thunderstorm Wind | Shabbona | $2,000 | Trees and power lines were blown down. |
| June 2013 | Thunderstorm Wind | Rollo | $2,000 | A Sheriff reported trees and power lines down in the area around Shabbona Road and Sleepy Hollow Road. |
| August 2006 | Thunderstorm Wind | Genoa | $2,000 | Tree limbs and power lines were blown down. |
| August 2018 | Thunderstorm Wind | Kirkland | $1,000 | A tree was blown down which took down a power line and some phone lines. |
| March 2017 | Thunderstorm Wind | Sandwich | $1,000 | Power poles were blown down by the high school. A home weather station observed a wind gust of 73 mph. |
| July 2017 | Thunderstorm Wind | De Kalb | $1,000 | Trees and power lines were blown down in De Kalb. A tree was blown down on a house on North 12th Street. |
| June 2017 | Thunderstorm Wind | Sandwich | $1,000 | A trampoline was thrown over a garage and two fences were destroyed. |
| May 2014 | Thunderstorm Wind | Malta | $1,000 | A power pole snapped and a pole barn received roof damage near Nelson Road and Malta Road. |
| July 2012 | Thunderstorm Wind | Wilkinson | $1,000 | Trees were blown down near Coltonville Road and 1st Street. Another tree was blown down near Bethany Road and 1st Street. The falling trees knocked down power lines. |
| April 2010 | Thunderstorm Wind | Hart | $1,000 | Trees were blown down along Route 72 on the west side of Genoa. Powerlines were also blown down. |
| July 2012 | Thunderstorm Wind | De Kalb | $500 | A large metal light pole was split and toppled at a gas station near Hillcrest Avenue and 1st Street. |