National Weather Service officials have issued a severe thunderstorm warning until 6 p.m. Tuesday for southern Illinois.
Areas under the warning include Northwestern Monroe County, Northern St. Clair County, Southern St. Louis City, Northeastern Jefferson County, South central St. Louis County.
The warning states those areas could see golf ball-sized hail and 60 mph wind gusts. Ameren has activated an Emergency Operations Center to respond to any outages caused by the severe weather Tuesday night.
“For your protection move to an interior room on the lowest floor of a building,” the NWS warning states.
A tornado watch has also been issued for the metro-east.
The following counties are under the watch until 9 p.m.: Alexander, Bond, Calhoun, Clinton, Edwards, Fayette, Franklin, Gallatin, Greene, Hamilton, Hardin, Jackson, Jefferson, Jersey, Johnson, Macoupin, Madison, Marion, Massac, Monroe, Montgomery, Perry, Pope, Pulaski, Randolph, Saline, St. Clair, Union, Wabash, Washington, Wayne, White and Williamson.
The metro-east could be in for two rounds of severe weather later Tuesday, according to a NWS meteorologist.
Thomas Spriggs with the National Weather Service in St. Louis said the first of the two rounds is expected to be the more potent of the two. That round of storms could come as early as 5 p.m. and last until 8:30 p.m.
“The first round is what worries us the most,” Spriggs said. “It has the potential for tornadoes and large hail that could be golf ball- or baseball-size.”
The chance of a second round of severe weather comes after midnight, Spriggs said. He said the chances of tornadic activity are not as good, but there is a chance for damaging straight-line winds.
The latest forecast said the chances of rain were 50 percent in the afternoon and increased to 80 percent in the evening. There was a chance the wet weather would stick around Wednesday morning.
According to a severe weather outlook, the greatest risk for severe weather was across southeast and east-central Missouri and southwest and central Illinois. Threats included large hail, damaging winds and tornadoes. Several strong, long-track tornadoes were possible. The NWS said storm-spotter activation was likely Tuesday afternoon.
Here’s a look at the seven-day forecast from the NWS:
Today ... A slight chance of showers and thunderstorms before 3pm, then a chance of showers and thunderstorms after 4pm. Some storms could be severe, with large hail and damaging winds. Mostly cloudy, with a high near 76. South wind around 17 mph, with gusts as high as 28 mph. Chance of precipitation is 50%.
Tonight ... Showers and thunderstorms, mainly before 5am. Some storms could be severe, with large hail and damaging winds. Low around 51. South wind 14 to 16 mph becoming west after midnight. Winds could gust as high as 29 mph. Chance of precipitation is 80%.
Wednesday ... A 20 percent chance of showers before 9am. Mostly cloudy, then gradually becoming sunny, with a temperature falling to around 50 by 5pm. West wind 15 to 17 mph, with gusts as high as 30 mph.
Wednesday Night ... Mostly clear, with a low around 32. Northwest wind 8 to 13 mph becoming light west after midnight. Winds could gust as high as 20 mph.
Thursday ... Sunny, with a high near 57. Light west wind increasing to 8 to 13 mph in the morning. Winds could gust as high as 23 mph.
Thursday Night ... Mostly clear, with a low around 26.
Friday ... Sunny, with a high near 49.
Friday Night ... Partly cloudy, with a low around 38.
Saturday ... Sunny, with a high near 63.
Saturday Night ... Partly cloudy, with a low around 46.
Sunday ... Mostly sunny, with a high near 67.
Sunday Night ... A 30 percent chance of showers. Mostly cloudy, with a low around 52.
Monday ... A 30 percent chance of showers. Partly sunny, with a high near 67.