St. Louis in January

April through June brings perfect weather and blooming flowers in Forest Park. The humidity hasn't kicked in yet, and outdoor festivals start picking up steam. September and October deliver crisp air and fall colors — ideal for walking the riverfront or exploring neighborhoods on foot. Summer gets sticky. July and August see temperatures pushing 90°F with humidity that makes it feel worse. But this is when the city comes alive — outdoor concerts, baseball season, and festivals every weekend. Just pack light, breathable clothes and plan indoor activities for the hottest part of the day. Winter can be brutal with ice storms and temperatures dropping below freezing. January through March sees fewer crowds and lower hotel rates, but many outdoor attractions close or reduce hours.