After filtering out repetitive reports, the SPC determined that 15 tornadoes formed in the Sunflower State in central and eastern Kansas, from the Gypsum Hills of Barber County to the Flint Hills of Chase, Lyon, and Morris counties.
The agency's Tulsa office says isolated tornadoes are possible as part of storms that will push through that part of the state.
Storms whipped through a wide swath of the nation's midsection, giving rise to tornadoes that flattened a Wisconsin mobile home park and an Oklahoma subdivision and killing at least two people and injuring dozens of others.
In the Tulsa area, severe storms are expected Thursday night and early Friday morning. Further south, in Oklahoma City and Stillwater, the risk is moderate. The risk of severe storms is enhanced in the Oklahoma City area, as well as in northeastern and southwestern Oklahoma. Flash flooding could be an issue with the stronger storms.More news: US, Saudi Arabia agree arms deal worth $110 billion
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Besides Wyandotte County, the other counties under the tornado watch include Leavenworth, Johnson and many surrounding counties, according to the weather service.
The National Weather service reported hail across the state Thursday night.
The weather service also forecasts a 20 percent chance of showers and thunderstorms today in Tulsa; a 60 percent chance overnight tonight; a 50 percent chance Friday; a 90 percent chance Friday night; and a 40 percent chance Saturday.
More than 4.5 inches of rain fell at Willard in Shawnee County, and 3.63 inches fell in a 24-hour period a few miles from Talmage in Dickinson County.