Historical weather data, all-time temperature records, and monthly climate averages for Florissant, MO. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 4th in Florissant splits the difference between winter's last gasp and spring's arrival — expect a high around 61° and a low near 41°, though 88 years of records show the date can swing wildly from 85° (1942) to a teeth-chattering 23° (1975). There's a 40% chance of rain today, so keep an umbrella handy, but snow is almost a non-issue at just 1%.
Florissant's weather has real teeth — the all-time high of 115° in July 1954 is one of the most brutal readings on record for the region, while a -18° low in January 1985 shows winters here don't always play nice. Rainfall can be violent too: a single day in July 2022 dropped 8.64 inches, and a March 2013 snowstorm buried the area under 12.4 inches.
Florissant runs hot in summer and cold in winter with little in between — average highs peak at 90° in late July and bottom out at 38° in mid-January, a 52-degree seasonal swing. If you're dodging rain, late June through early July is the wettest stretch of the year, averaging over an inch of precipitation per week. Spring and fall offer the most comfortable travel windows, with April and October both averaging highs in the mid-to-upper 60s.