From March 13–17, 2026, a large and powerful extratropical cyclone produced a variety of significant weather across the Central United States and portions of southern Canada, consisting of a major and historic blizzard – which was unofficially referred to as Winter Storm Iona by the Weather Channel and other media – that affected much of the Upper Midwest and High Plains with up to of snow, an ice storm over northern Michigan and a severe weather outbreak consisting of damaging winds, large hail and tornadoes across the Lower Mississippi Valley, the Southeastern United States, the Carolinas, and the Mid Atlantic states. The overall system first moved onshore in the Pacific Northwest on March 13, dumping heavy snowfall primarily over the mountainous regions there. Emerging off the Rocky Mountains late on March 14, the storm strengthened as it moved northeastwards.
Widespread winter weather alerts, including winter storm warnings and blizzard warnings were issued from the state of Washington to Wisconsin and the Upper Peninsula of Michigan. Many governors, primarily in the Upper Midwest, issued states of emergencies as forecasts of were expected in the heaviest accumulations. Hundreds of flights were cancelled across the states of Minnesota and Wisconsin as well. On the severe side of the system, the Storm Prediction Center on March 15 issued an enhanced risk of severe weather across the South, with multiple tornado watches issued. The outbreak was expected to continue into the next day in the Carolinas and Mid-Atlantic, with a moderate risk of severe weather forecast.
As of March 16, at least three fatalities have been confirmed as a result of the winter weather side of the system, and at least 500,000 people were estimated to have lost power. Total damage costs were estimated to be approximately US$1.4 billion. It is the first storm to be rated as a Category 5 on the Regional Snowfall Index since the January 2016 United States blizzard.
Meteorological history
On March 12, an atmospheric river interacted with Arctic air from Canada, producing snowfall across the northern United States Rockies and the northern High Plains on March 13. Throughout March 14, the system moved eastwards slowly deepening, before evolving into a Colorado low as a surface low emerged from the Rocky Mountains. By 03:00 UTC on March 15, the Weather Prediction Center (WPC) began issuing periodic storm summary bulletins on the developing storm. The storm produced blizzard conditions over parts of the Upper Midwest and Great Lakes on March 16, attaining a pressure of over Michigan at 12:00 UTC. Blizzard conditions began to wind down for the Upper Midwest and Great Lakes and the WPC issued its last storm summary at 03:00 UTC on March 17.
The storm intensified as it moved through Quebec, deepening to a pressure of by 06:00 UTC on March 18 as it moved offshore into the Labrador Sea. Afterwards, the system weakened and made landfall in Greenland by 03:00 UTC on March 19.
Preparations and impact
United States Winter storm warnings and blizzard warnings were issued for a wide swath of the northern tier from Washington to the Upper Peninsula of Michigan, with the latter type being issued for most of the states of Iowa, Wisconsin, Minnesota, South Dakota and portions of northern Michigan. Ice storm warnings were issued for the northern Lower Peninsula of Michigan. Red flag warnings were issued for the southern Plains due to strong winds and dry air forecasted in the wake of the storm. Over 500,000 lost power across the United States. By the morning of March 16, 5,000 flights were cancelled from the day prior.
Pacific Northwest Seattle, Washington received a rare period of snow on March 13, with as much as falling as a result. Roadways such as Interstate 90 were closed but disruptions were minor. Hundreds of flights ended up being delayed at the Seattle-Tacoma International Airport. The airport set a snowfall record of and a rainfall record of for March 13. The Olympia Airport recorded of rain also setting a record that day. At higher elevations where heavier snow fell in the mountains, mountain passes were closed. Roughly of snow fell in the Snoqualmie Pass while around of snow was reported at the summit of Snoqualmie. I-90 in the Snoqualmie Pass closed due to multiple spinouts and crashes.
Windy conditions led to nearly 5,000 customers without power in the Treasure Valley area of Idaho. In Montana, heavy wet snow led to tree branches falling causing numerous power outages across the western parts of the state. of snow was recorded near Cooke City, Montana.
Upper Midwest Minnesota declared a peacetime emergency on March 13, with Governor Tim Walz authorizing the Minnesota National Guard for emergency preparedness, where of snow was forecasted in Minneapolis. Delta Air Lines cancelled numerous flights ahead of the storm from Minneapolis-St. Paul International Airport. Xcel Energy stated that they were ready to assist in recovery efforts and power restoration during the storm. The city of Duluth advised residents to stay off the roads, while snow crews were readied to be deployed starting at 2 a.m. on March 15. Minnesota State Patrol reported 464 crashes between March 13 at midnight to March 15, with 40 involving an injury and one fatal. Parts of southern Minnesota received over of snow with Kellogg recording of snow.
On March 14, Wisconsin Governor Tony Evers declared a state of emergency. The city of Marshfield declared a snow emergency in effect from March 15 to 16, and closed numerous public libraries and churches on March 15. Wausau set a daily snowfall record on March 15 with of snow recorded. The city also set a three-day snowfall record as well with of snow falling from March 14 to 16. Green Bay also set a daily record of of snow for March 15. A total of of snowfall was recorded at the Green Bay National Weather Service station, the second-highest on record only behind an early March 1888 storm. Several communities recorded of snow with reported in Mountain. I-94 in Jackson County closed after two semi trucks became stranded on March 15. By 5 a.m. on March 16, 13,256 customers lost power across southeast Wisconsin. The Wisconsin State Patrol reported over 90 crashes, 11 of which resulted in injuries.
The Michigan State Emergency Operations Center was activated by Governor Gretchen Whitmer on March 15. 140,000 customers lost power in the state due to the storm on March 16. The highest recorded storm-related snow total in the state came from Round Lake in the state's Upper Peninsula, which saw . In areas mostly populated, Negaunee received , Gwinn got , and Menominee saw . Meteorologists at the Marquette National Weather Service station (actually located in Negaunee Township) reported that the storm dumped of snow on their location over a two-day period; surpassing their previous two-day record total, set in 1997, by nearly . Near Grayling, of freezing rain was recorded. Due to the snowfall, Governor Gretchen Whitmer declared a state of emergency for seven counties on March 17.
The blizzard brought dangerous road conditions to Iowa. Parts of I-80 and I-35 were closed due to crashes. The Iowa State Patrol responded to 99 crashes and assisted 299 motorists between March 15 and 16 at 9 a.m., totaling to 398 calls for service. Of the crashes, 86 resulted in damage, 12 in injuries, and one was fatal. of snow was recorded in Lowden. Freezing rain accumulations also occurred in the state with of freezing rain reported in Sioux Rapids.
A fatal crash occurred in Lancaster County due to whiteout conditions on March 15. The Nebraska State Patrol reported an additional five crashes. They had also assisted 43 motorists and six other responses by other agencies. Elsewhere in Nebraska, the windy conditions produced by the storm helped fuel fires in the state.
Heavy snow and strong winds caused parts of I-29 and I-90 to close in South Dakota. A number of car accidents were reported by first responders. A total of of snow was recorded near Spearfish. Further north in North Dakota, of snow was reported in Gladstone.
Prior to the snowfall, severe weather led to O'Hare International Airport and Midway International Airport to issue a ground stop on March 15. Flooding was reported in parts of Illinois due to heavy rainfall. Lanark recorded of snowfall.
Ohio Valley and Appalachians A cold front attached to the low pressure in the Upper Midwest brought snow to many areas across the Ohio Valley and the Appalachians on the evening of March 16th, after plummeting the region by in just 36 hours. Several counties in Ohio declared snow emergencies due to the winter weather, with accidents resulting in delays or road closures. Charleston saw roughly of snow, with many accidents occurring due to the weather. Meanwhile, Pittsburgh saw of snow, its second highest snow-event total of the winter season. This set the all-time record for snow accumulation amounts on a day or higher for Pittsburgh, prompting school delays and closures the following Tuesday.
Additionally, strong winds occurred throughout the region, causing damages and widespread power outages. A gust of was recorded in Fort Wayne. By 9:30 p.m. on March 15, approximately 9,000 outages were reported across the state. Over 46,000 lost power in Kentucky due to the storm on March 15. Icy conditions led to crashes and the closure of roads on March 17. The Lexington Police Department reported a total of 277 crashes, 16 of which resulted in injuries. A peak of 7,700 lost power in East Tennessee on the morning of March 16, with snow resulting in school closures the following day.
South Multiple tornado watches and warnings were issued across many states. A damaging squall line went through many Southern states.
Damaging winds from thunderstorms of over occurred in Missouri. Tree damage occurred in the state.
On the evening of March 15, over 50,000 lost power in Arkansas.
Winds blowing debris onto the road prompted I-35E in Denton to briefly close on March 15. The Java House Grand Prix of Arlington cancelled a concert, including Six Flags Over Texas being closed. Approximately 30,000 lost power in North Texas. The Dallas-Fort Worth International Airport saw flight delays. The Bullfrog Marina on Lake O' the Pines sustained heavy damage. Over 2,000 lost power in East Texas.
Mid-Atlantic Maryland Governor Wes Moore declared a state of preparedness ahead of the severe weather on March 15. Early closures for March 16 were announced for several schools. Localized flooding occurred in Baltimore and wind damage was reported in parts of the state. Over 16,000 power outages were reported by Baltimore Gas and Electric by 11 p.m. on March 16.
Severe storms impacted Delaware. Roughly 6,000 Delaware Electric Cooperative customers lost power while Delmarva Power had 5,421 outages by 3:00 a.m. on March 17.
In northwestern Saylorsburg, Pennsylvania, 869customers of Met-Ed reported a power outage early on March 16. A tree fell and killed a man while removing a different tree in Newton Square.
In New York, John F. Kennedy International Airport had a peak gust of . Strong winds brought down trees in the state. A driver died in a crash after trying to swerve around a fallen tree and lost control in Mount Pleasant.
A peak gust of occurred in Newark, and a gust was recorded at Avalon. On the morning of March 17, almost 38,000 were reported to have lost power. NJ Transit suspended some rail lines due to downed trees.
New England Severe weather led to many road closures in Connecticut. Almost 31,000 lost power by 7:45 a.m. on March 17. Several schools in the state had delays.
A total of nearly 15,000 costumers lost power in Rhode Island on March 17.