Record Warmth Meets Severe Storm Threat: A Volatile Tuesday for St. Louis

Morning Fog and Rapidly Rising Temperatures

St. Louis residents are beginning Tuesday, March 10, 2026, with a mix of limited visibility and unseasonable warmth. The National Weather Service has issued a Dense Fog Advisory for the metro area and surrounding counties in eastern Missouri, effective until 9:00 AM. Commuters should prepare for visibility dropping to a quarter-mile or less in some pockets, making for a slow morning drive. Despite the fog, the day is starting at a balmy 62°F, setting the stage for a significant warmup throughout the morning hours.

Afternoon Record Heat and SSW Winds

By early afternoon, the fog will give way to a mostly cloudy sky, but the real story is the heat. St. Louis is expected to see near-record warmth today, with high temperatures reaching between 82°F and 85°F. These temperatures are significantly above the seasonal average for early March. To accompany this heat, winds will persist from the south-southwest at approximately 15 mph. While the first half of the day will remain dry, the humidity will hover around 70%, creating a volatile atmosphere that will fuel potential weather developments later this evening.

Severe Thunderstorm Threat Tonight

The primary concern for the St. Louis region involves a Weather Impact Alert for the late afternoon and evening hours. As a cold front approaches, the Storm Prediction Center has placed the area under a severe weather risk. Here is what to expect as the day progresses:

• Timing: Storms are expected to begin developing across Missouri around 4:00 PM, with the most intense activity likely hitting the St. Louis metro and the Metro East between 7:00 PM and midnight.
• Wind and Hail: Forecasters are warning of damaging wind gusts exceeding 60 mph and a significant threat of large hail. Some isolated supercells could produce hail up to 2.75 inches in diameter, roughly the size of a tennis ball.
• Tornado Risk: While the highest tornado threat is projected for northeast Missouri and west-central Illinois, rotating cells capable of producing tornadoes are possible in the St. Louis area and the Metro East.
• Heavy Rain: Locally heavy downpours may lead to quick rises on creeks and streams, potentially causing minor flooding in low-lying areas.

Safety and Overnight Outlook

As the front moves through, temperatures will begin to drop, settling into a low of 61°F to 62°F overnight. Residents are urged to have multiple ways to receive weather warnings tonight, especially as the severe threat may continue into the late-night hours. Secure any outdoor furniture or loose items this afternoon before the wind gusts intensify. Looking ahead to Wednesday, the severe threat will ease, but a drenching rain is expected to impact the morning commute as the system completes its passage through the region.