On January 16, 2023, Iowa experienced a rare meteorological event as two tornadoes touched down in the eastern part of the state, marking the first January tornadoes in Iowa in 56 years. According to the National Weather Service (NWS), the last time Iowa saw January tornadoes was in 1967 — with a total of 13 tornadoes during the month. While tornadoes are a relatively common occurrence in Iowa, with peak season typically taking place in May, January tornadoes are a rare phenomenon.
The severe weather outbreak on January 16 was caused by a large low pressure system that spun northeast across Iowa, drawing mild temperatures northward and sparking some showers and thunderstorms over portions of eastern Iowa. The warm temperatures, clear skies, and increased moisture levels provided the perfect conditions for the formation of severe thunderstorms.
One storm, in particular, was particularly severe, producing two tornadoes between 14:00 CST and 15:00 CST. The first tornado touched down just northeast of Williamsburg and the second one briefly touched down north of Ely.
The Williamsburg tornado developed south of Interstate 80 and blew over a semi-tractor trailer on the highway before moving northeast. The tornado caused minor damage to a cattle shelter and tree damage at a farmstead before lifting near U.S. Highway 151. It was on the ground for approximately 8 minutes and traveled a path of approximately 7.5 km (4.7 miles) with a maximum width of 365 m (400 yards). The tornado was rated as an EF1 on the Enhanced Fujita Scale with estimated peak winds of 145 km/h (90 mph).
The second tornado was reported by a storm chaser north of Ely, Iowa. The tornado was on the ground for about 1 minute. There was no observable damage reported, making it impossible to assign a rating or to estimate its peak winds or path length. The maximum width of the tornado is also unknown.
There were no injuries or deaths reported as a result of the tornadoes.
The storm also produced large hail, with reports of hail up to 0.6 cm (0.25 inches) in diameter in Homestead and other areas.
These tornadoes were the first reported in Iowa in the month of January since January 24, 1967.
Meteorologist Tim Gross from the NWS Quad Cities office explained that “all the severe weather ingredients came together for it to occur.” He added that warm temperatures, clear skies and increased moisture levels, coupled with an upper level low pressure system and enough wind shear, caused some of the storms to rotate and produce tornadoes.
While January tornadoes in Iowa are a rare occurrence, this is not the first time that the state has seen tornadoes in the winter. On December 15, 2021, the December Derecho produced 63 tornadoes, the largest tornado outbreak on record in Iowa.
It’s important to note that Iowa has a long history of tornadoes, with an average of around 50 tornadoes per year. The state is part of what is known as Tornado Alley, a region in the central part of the United States that is known for its high frequency of tornadoes. While tornadoes can happen at any time of the year, they are most common between April and June.
The year with the most tornadoes in Iowa was 2004 with 120 tornadoes, followed by 2021 with 114, and 2008 and 2001 with 105.