Severe Weather New Updates: St. Louis and Metro East Under Threat, Large Hail, Tornadoes, and Damaging Winds Expected For Friday Afternoon

Residents of St. Louis, Missouri, and the Metro East region of Illinois should prepare for a significant severe weather event on Friday afternoon as the National Oceanic and Atmospheric Administration’s (NOAA) Storm Prediction Center has issued a Moderate Risk alert for the area.

The National Weather Service (NWS) St. Louis office forecasts the development of severe thunderstorms beginning around 1 p.m. CDT, affecting east-central and southeastern Missouri, including the greater St. Louis metropolitan area and extending into the Metro East counties.

Primary hazards expected include very large hail over 2 inches in diameter, damaging wind gusts up to 80 mph, and the possibility of strong tornadoes rated EF2 or greater.

The NOAA Storm Prediction Center has issued a tornado watch covering portions of southern Illinois and central to eastern Missouri through 7 p.m. CDT. Meanwhile, the NWS is issuing localized severe thunderstorm and tornado warnings as storms develop and move through the region.

According to the National Weather Service (NWS) St. Louis, severe thunderstorms are expected to begin forming near 1 p.m. CDT across east-central and south-central to southeast Missouri, stretching from just west of the St. Louis metropolitan area eastward along and beyond Interstate 44.

The main threats associated with these storms include:

The SPC is responsible for issuing tornado and severe thunderstorm watches, alerting residents of areas where conditions are favorable for severe weather development. Local warnings—severe thunderstorm warnings and tornado warnings—are issued by the NWS St. Louis office as storms form and intensify.

As of the afternoon on May 16, a Severe Thunderstorm Warning was active for parts of southeastern Calhoun County, Illinois, northeastern Saint Charles County, and Saint Louis County and City. This warning remains in effect until 2:45 p.m. CDT and highlights immediate threats of two-inch hail and wind gusts around 60 mph.

Simultaneously, a Tornado Watch covers portions of southern Illinois as well as central and eastern Missouri from 11:55 a.m. through 7:00 p.m. CDT. This watch area extends approximately 80 statute miles east and west along a line from 70 miles south of Harrison, Arkansas, to 35 miles north-northwest of St. Louis, Missouri.

At 2:02 p.m. CDT, a severe thunderstorm was reported over Defiance, Missouri, approximately 7 miles southwest of Dardenne Prairie, moving eastward at 55 mph. Areas impacted include:

The storm environment continues to become more conducive to severe weather due to:

Supercell thunderstorms are distinguished by their rotating updrafts and are capable of producing all forms of severe weather hazards, including large hail, damaging winds, and tornadoes.

According to the National Weather Service, such storms pose significant threats:

The NWS St. Louis office encourages residents to maintain situational awareness, have a weather radio or smartphone alerts enabled, and know their safest shelter options.

The Federal Emergency Management Agency (FEMA) and the National Oceanic and Atmospheric Administration (NOAA) provide the following guidance for residents in tornado and severe storm risk areas:

For more detailed preparedness information, visit official websites:

The St. Louis metropolitan area has a history of impactful severe weather outbreaks, including notable tornadoes and damaging hail events. The Missouri State Emergency Management Agency (SEMA) underscores the importance of preparedness given the region’s vulnerability during spring and early summer.

This year’s increasing atmospheric instability is consistent with seasonal patterns, where warm, moist air from the Gulf of Mexico collides with cooler air masses from the north, setting the stage for intense thunderstorms.

Local emergency services, including the St. Louis County Office of Emergency Management and the Illinois Emergency Management Agency (IEMA), are coordinating with the National Weather Service and other partners to provide timely alerts and facilitate rapid response in the event of storm impacts.

Residents are urged to heed all warnings and instructions from authorities, report hazardous conditions, and check on neighbors, especially the elderly or those with mobility challenges.

The severe weather outlook also affects schools and businesses in the region. Institutions are advised to review their severe weather protocols, communicate plans with staff and students, and ensure that safe shelter areas are accessible.

The St. Louis Regional Chamber recommends businesses monitor weather forecasts closely and be prepared for possible disruptions, including power outages and transportation delays.

As severe weather approaches the St. Louis metropolitan area and Metro East region, residents and visitors are urged to prepare and respond quickly to warnings. The combination of very large hail, damaging winds, and potential tornadoes presents a serious hazard, and staying informed through trusted government and meteorological sources is critical.

By following official guidance from the National Weather Service, NOAA, and local emergency management agencies, communities can reduce risk and protect lives and property during this potentially dangerous weather event.