By , AccuWeather senior meteorologist
Published Jun 27, 2023 2:06 PM EDT | Updated Jun 29, 2023 5:39 AM EDT
AccuWeather meteorologists are monitoring the potential for a high-powered, long-tracking and fast-moving batch of thunderstorms, known as a derecho, to develop later this week across parts of the central United States.
In simple terms, a derecho behaves like an inland hurricane with a large batch of damaging winds and heavy rainfall that can at times lead to significant flooding.
The National Weather Service has developed criteria to distinguish derechos from other less intense and shorter-distance thunderstorm complexes. In order for a derecho to be declared, usually via a post-storm analysis, the storms must have traveled 400 miles or more with a width of at least 60 miles. The storms also must have produced damage nearly continuously along that path.
However, there will still be a significant risk to lives and property from a complex of severe thunderstorms this week — whether a derecho is officially declared or not.
"Complexes of thunderstorms will erupt near and north of the rim of tremendous heat, which is anchored over Texas and the southern Plains this week," AccuWeather Senior Meteorologist Dan Pydynowski said. "One day and night in particular — Thursday — may represent a higher risk for a derecho."
The first storms are likely to erupt Thursday afternoon, and there are two zones where a derecho may develop, AccuWeather forecasters say.
Complex of severe storms likely for central Plains Thursday
"Data suggests that much of Nebraska, northern Kansas, northwestern Missouri and southwestern Iowa will be one area at greatest risk for severe thunderstorms during Thursday afternoon and evening," Pydynowski said. Some of the first storms may erupt in portions of eastern Colorado and Wyoming as well.
From this zone, should an intense complex of storms evolve, it may continue to roll through the late-night hours Thursday and then across the middle portion of the Mississippi Valley and then perhaps into portions of the Ohio or Tennessee valleys Friday.
"The exact initial eruption of thunderstorms on Thursday and their intensity will determine how long they may survive and which areas may be hit or missed by the complex hundreds of miles away a day later," AccuWeather Senior Meteorologist Brett Anderson said. It is possible a long-lived complex such as a derecho could reach as far as parts of the southern and central Appalachians.
Midwest also at risk of severe thunderstorms
At roughly the same time Thursday, thunderstorms will erupt and may try to organize into one or more complexes in portions of Wisconsin, Illinois, southern Michigan, Indiana, western Ohio, Kentucky and Tennessee.
These storms may then roll southeastward with the core of the heat to the southwest and more temperate air to the northeast through Thursday night and into Friday.
Because there are multiple areas where thunderstorms could merge into dangerous and far-reaching complexes, it is possible that some places could be hit by two rounds of dangerous thunderstorms in 12 hours.
Just as all thunderstorms are not created equal, the same is true for derechos.
On Aug. 10, 2020, an intense derecho produced a swath of high winds and leveled crops from eastern Nebraska to parts of Michigan and northern and central Indiana. The damage swath extended for nearly 800 miles with a peak wind gust of 126 mph recorded in Atkins, Iowa.
The derecho raced eastward across the Midwest, causing destruction along its path on Monday, Aug. 10, 2020. (NWS Chicago)
That derecho resulted in at least four fatalities and more than $11 billion in damages across the Midwest.
On June 29, 2012, one of the most powerful derechos in recent memory caused substantial damage to the Washington, D.C., area. The storm produced significant wind damage along an 800-mile path from Iowa to the Delmarva Peninsula.
By the extended Independence Day weekend, the heat dome over the South Central states will break down and the risk of a derecho should lower. However, as weather systems continue to move along from west to east across the nation, there will still be episodes of thunderstorms, including large complexes of severe weather, in the central region through July 4.
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