Seasonably warm and dry weather continues for the start of October
As high pressure dominated the forecast for the majority of September, it led to a dry and warm start to the fall, compared to the same month in previous years.
The daily high temperatures measured through September resulted in an average temperature of 84 degrees for the entire month. Comparing this to the normal average of 80.1 degrees from previous Septembers, this is almost 4 degrees warmer than expected.
As for rainfall, the total for the entire month amounted to 2.06 inches, whereas the normal for September in previous years averages to 3.83 inches. This means that Columbia received almost 2 inches less rainfall than what would be anticipated for this past month. This has led to drought conditions emerging across the state, with nearly all of Missouri noticing dry conditions, and around 64% of Missouri experiencing some level of drought.
This dry, summer-like weather has not budged much to start October. Temperatures this afternoon neared 86 degrees, while the average high temperature for the start of October in Columbia is 74 degrees. This means that today's high temperature was over 10 degrees higher than it usually is for the start of the month.
This emergence of warmer-than-average weather in the fall is not new, as the entire nation has experienced a gradual increase in temperatures over the seasonal average from 1970 to 2024. The western United States has seen it the worst, as they have seen a 4-degree or greater increase in temperatures over this time period. Missouri, as a state, averages a 2 to 3 degree increase in fall temperatures from 1970 to 2024.
This has led to more days on average during the fall season being measured above the normal for that time of the year. In Columbia, the 1991-2020 average for fall days above normal has increased to nine or more days each fall season. This fall season so far, more than half of the afternoon high temperatures have been measured above the average for this time of year, with today, Oct. 1, included. This well exceeds the average of nine days.
This seasonably warm weather is set to continue throughout October, as the monthly temperature outlook still keeps Central Missouri above the average temperature for this time of year. This does not mean that afternoon high temperatures will continue to stay in the mid-80s, as losing total time in the sunlight each day will aid in less time to heat up.
Average high temperatures based on previous years for October get down into the upper 60s. This means that with above-average temperatures expected to continue, it can at least be expected to gradually get back down into the low to mid-70s.
