Warm Weather Months in Missouri: May Through September

In Missouri, the warm season typically spans five months:

• May – Spring warmth arrives; highs 70s–80s°F (21–29°C).
• June – Early summer; 80s–low 90s°F (27–34°C); humidity rises.
• July – Peak heat; highs often 90s°F (32–37°C); high humidity.
• August – Sustained heat; similar to July; occasional heat waves >100°F (38°C).
• September – Early fall; 80s°F (27–32°C); humidity drops; pleasant.

April and October are transitional (60s–70s°F). November–March are cool to cold, with winter lows below freezing.