St. Louis, Missouri – St. Louis residents woke up to a sharp blast of winter cold Monday morning as Arctic air settled across eastern Missouri before sunrise. Temperatures near 13°F were recorded at Lambert International Airport, with wind chills in the single digits, making it one of the coldest mornings so far this December. Icy air crept into neighborhoods across the metro area, turning early commutes into a test of patience and preparation.
Bitter Cold Starts the Day
The frigid start brought classic winter scenes across St. Louis. Car doors resisted opening, breath turned instantly visible, and untreated surfaces felt slick in shaded areas. According to the National Weather Service, the coldest conditions occurred just before dawn, when light winds allowed temperatures to drop quickly.
Despite the early chill, sunshine is playing a key role in recovery. As the sun climbs higher, temperatures are expected to rebound into the low 40s, offering noticeable relief by afternoon. Still, officials urge drivers to remain cautious, particularly on bridges, overpasses, and shaded roadways, where overnight frost may linger longer.
Homeowners are also advised to check exposed pipes, and pet owners are encouraged to keep animals indoors during the coldest hours.
Sunshine Brings Temporary Relief
By late morning and into the afternoon, brighter skies help ease the harsh conditions. Roads improve as surface temperatures rise, and outdoor activities become more manageable. While the daytime warmth helps, meteorologists note that winter hazards do not disappear entirely.
Cold ground temperatures mean that any lingering moisture can refreeze overnight, especially in low-traffic areas. Drivers heading out early Tuesday morning should stay alert for isolated slick spots.
Milder Air Arrives Tuesday
A noticeable shift in the weather pattern begins Tuesday as southerly winds pull milder air into the region. Afternoon highs climb into the low 50s, well above Monday’s readings. Sunshine dominates much of the day, accelerating snowmelt across the metro.
That melting snow leads to damp pavement, which becomes a key factor later in the week as rain enters the forecast. While Tuesday itself remains dry, the groundwork is set for changing road conditions.
Midweek Warm Surge Raises Rain Concerns
By Wednesday, temperatures surge into the mid-50s, far above normal for mid-December. Increasing cloud cover signals the next system approaching the Midwest. Rain chances rise Wednesday night as moisture streams northward.
Forecasters are closely monitoring how quickly colder air follows this system. While precipitation is expected to begin as rain, the timing of the temperature drop will determine how conditions evolve late in the week.
Thursday Brings Travel Risks
Thursday is shaping up to be the most impactful day for commuters. Showers remain likely during the morning hours, gradually tapering off by midday. Early afternoon temperatures may still feel mild, but a sharp cooldown follows late in the day.
By Thursday night, readings are expected to plunge into the low 20s. Any leftover moisture on roads could flash freeze, creating hazardous conditions for evening and early Friday travel. Major corridors such as I-64, I-70, and I-55 are particularly vulnerable to rapid icing.
Transportation officials urge drivers to reduce speed, increase following distance, and remain alert for sudden changes in road traction.
Cooler but Calmer to End the Week
Behind the departing system, winter regains control. Friday turns mostly sunny but colder, with highs near 37°F. Conditions stabilize heading into the weekend, with quieter weather expected Saturday and a brief return to milder afternoon temperatures before another cooldown on Sunday.
Five-Day Outlook for St. Louis, Missouri
• Today: Sunny after a frigid morning, high near 41°F
• Tuesday: Sunny and milder, high near 51°F
• Wednesday: Warmer with rain late, high near 54°F
• Thursday: Showers early, colder late, high near 58°F
• Friday: Sunny and colder, high near 37°F
Plan Ahead for December Whiplash
This week’s forecast highlights the classic December temperature swings common across the Midwest. Residents should plan ahead for wet roads midweek and freezing risks shortly afterward. Staying weather-aware can help reduce travel disruptions and safety concerns as conditions change rapidly.
Have you noticed the dramatic temperature swings where you live? Share your experiences in the comments below.
