March is really going to roar in like a lion for many people this year. Severe storms are expected to develop along a strong cold front Tuesday night and quickly move eastward through Wednesday afternoon. Tornadoes, damaging winds, and large hail will be possible with these storms. Behind the front, much colder air and some snow will move into the Great Lakes for Thursday.
Showers and thunderstorms are currently ongoing across the Ohio Valley this morning, with a small thunderstorm or two across Illinois. Later this afternoon and evening, additional thunderstorms will develop along a cold front currently across Iowa, Nebraska, and Kansas. These storms will continue to develop and intensify in the warm sector just ahead of the cold front overnight tonight.
Some of the storms that develop this afternoon ahead of the cold front will become severe with large hail and a few tornadoes being possible. The best chance for this activity is across Illinois, Indiana, parts of Western Ohio, and as far south as southwestern Missouri and northern Arkansas. As storms develop along the cold front tonight across northern Missouri, northern Illinois, and parts of Kansas, a tornado threat will also exist before the storms begin to transition into a squall line. It is possible that a few strong tornadoes may develop across portions of Illinois, Indiana, and southwestern Missouri.
Overnight, these storms will evolve into a fast-moving squall line and the primary severe weather threat will transition to widespread damaging winds across the Ohio Valley and into the Mid-Atlantic by Wednesday afternoon. An isolated tornado or two cannot be ruled out along the line of storms as it moves eastward. Additionally, another complex of showers and thunderstorms will have developed ahead of this squall across the Ohio Valley, which could limit the overall severity of the squall line across Ohio. However, some of the storms that develop across Indiana and Ohio could be severe with large hail and an isolated tornado possible. Damaging wind gusts are also possible. This activity will have to be closely monitored.
Here’s a loop of the thunderstorms from this evening through Wednesday afternoon:
The SPC Day 2 outlook shows the best threat for severe weather across parts of the Ohio Valley into the Tennessee Valley and as far south as Alabama and Mississippi. Damaging winds will be the main threat with the line of storms racing across this region Wednesday morning and afternoon, with an isolated tornado also possible. A slight risk for severe storms is in place for the Mid-Atlantic and Jersey shore. As the storms approach the East Coast late Wednesday afternoon and early evening, they will begin to lose their strength and gradually diminish in both intensity and coverage.
Some of the cells embedded within the squall line could become discrete across parts of Ohio, Kentucky, and West Virginia Wednesday morning and early afternoon. Any discrete cells that do develop will also be capable of producing large hail and a tornado or two.
As the storms move eastward Wednesday afternoon, they will diminish in intensity heading toward the East Coast. By Wednesday night, some of the remaining storms may be strong to briefly severe with primarily a damaging wind threat.
Behind the cold front, snow will move into the Great Lakes Wednesday night and diminish early Thursday morning. An inch or less of snow is expected. Highs will only be in the 30s on Thursday after highs in the 60s on Wednesday.