Dangerous severe storms will sweep across the eastern half of the US this Memorial Day weekend, hitting several major cities Saturday through Monday.
The storms begin Saturday, with 18 million people from Texas to Iowa under a major threat of severe storms, the strongest of which will hit Oklahoma, Kansas and Missouri, including Oklahoma City and Tulsa, Oklahoma; Joplin, MO; and Wichita, Kansas.
Thunderstorms over Oklahoma and Texas are expected to move east toward Missouri and Iowa overnight. Some long-lived supercells are also expected. These storms can produce intense tornadoes, giant hail, and destructive wind gusts.
Clusters of these supercells will merge, creating larger storm systems overnight in northern Oklahoma and central and eastern Kansas, the National Weather Service said on cases of flash flooding” will be possible until midnight.
The storms will move further east on Sunday, moving into the Midwest and the Ohio Valley. They are expected to affect 42 million people in cities including Chicago, Indianapolis, Nashville, St. Louis and Cincinnati.
Damaging winds are most expected in the Midwest, but tornadoes and large hail are also possible.
The storms will end on the East Coast on Monday, with a slight risk of severe weather in the mid-Atlantic. In this region, including Baltimore; Washington, DC; and Charlotte and Raleigh, North Carolina, 27 million people are at risk of experiencing strong to severe thunderstorms.
The main hazard to look out for is high winds, but one or two storms could produce large hail or a tornado.
With this active storm pattern, there is a risk of flash flooding, especially in the central Mississippi Valley. In total, 3 million people are under flood warnings, including in cities such as Memphis, Tennessee; and Tupelo, Mississippi.
Precipitation totals will generally range from 1 to 2.5 inches through the weekend, with locally higher amounts of over 3 inches possible as training storms develop.
Southern heat
While the South won’t experience thunderstorms over Memorial Day weekend, it will experience extreme heat.
Summer temperatures will impact the Southern Plains and Gulf Coast, with highs rising 10-20 degrees above average.
Heat warnings are in effect Saturday for 7 million people in south Texas, including in Austin, San Antonio, Corpus Christi and Brownsville, as temperatures could reach 100-115 degrees.
Nearly two dozen record highs will be threatened Saturday afternoon as temperatures reach 90-100 in Brownsville and Houston, Texas; Key West, FL; and New Orleans.
Both Brownsville and Harlingen, Texas, set new daily high records on Saturday, with Brownsville reaching 99 degrees and Harlingen at 100 degrees, according to the NWS, both 2 degrees higher than their previous records.
More heat will hit the South on Sunday, with more than two dozen record highs threatened in Corpus Christi; Miami and Orlando, Florida; Baton Rouge, Louisiana; Dallas, Houston and San Antonio.
Extreme fire conditions
Four million people have been warned of critical fire conditions in the High and Southern Plains from Colorado to Texas, including Albuquerque and Santa Fe, New Mexico; and El Paso, Texas.
Newly formed fires are at risk of spreading rapidly due to the dangerous combination of dry vegetation, wind speeds of 50 to 70 km per hour and low relative humidity.
This article was originally published on NBCNews.com
