By Chuck Otte
Geary County Extension Agent, Retired
If you thought that September was a bit warm, you were correct. In fact, with a monthly mean temperature over 9 degrees above average, it was our hottest September on record. And while the first half of the month was dry, the second half of the month put us above average for September.
The average daily high during September was 86.8, 6.4 degrees above normal. The average overnight low was 69.8, 12.3 degrees above normal. This gave us a monthly mean temperature of 78.3, 9.4 degrees above the long term average. The previous hottest September on record was in 1954 with a monthly mean temperature of 78.1, solidly cementing September 2026 as the hottest September on record.
Not coincidentally, It was the hottest September on record for the entire state and all nine of the state reporting districts. It was also the 13th consecutive month with monthly mean temperatures above average. The overnight low temperature of 69.8 was also the warmest average overnight low on record for the region.
The hotter than normal September also falls into a concerning recent trend. Four of the six hottest Septembers on record have occurred since 2019 (2019, 2021, 2023 and 2026), The coldest September on record was in 1974 with a monthly mean temperature of 61.1 degrees. Over the last 30 years, the region experiences just under 6 days during the month with temperatures of 90 or above. This year we had 15 days with temperatures of 90 or above.
The highest temperature for the month was the 102 degree high on the 8th. The coldest temperature for September was 60 degrees on the 23rd and 24th. Naturally, there were temperature records set and tied during September. The high of 97 on the 14th broke the old record high for that date set in 1955. The overnight lows of 76 on the 1st and 3rd tied the record high lows for those dates set in 2011 and 2000 respectively.
The following were new record high low temperatures: 76 on the 8th and 9th broke the old records of 74, on both dates, set in 1964 and 1955/2019 respectively; 81 on the 15th broke the old record of 73 set in 1955 (and is the warmest and only high low temperature above 80 for the month of September) and 78 on the 18th broke the old record of 76 set in 2022.
With high temperatures running well above normal for the first ten days of September it was quite concerning that there was no significant precipitation during this period. It was almost half way through the month before the rains began. Long term average September rainfall is 2.85 inches. September 2026 received 4.5 inches of very welcome rain and a return to seasonal temperatures. The driest September on record was in 1947 when only 0.24 inches was recorded. Twenty years later, 1967, the region saw it’s wettest September on record with 13.28 inches of rainfall. That was the only year that September rainfall exceeded ten inches.
Year to date the region has received 33.85 inches of precipitation, well above the average of 28.50 through the first nine months of the year. In fact, 33.85 inches is slightly more than our long term average annual precipitation of 33.57.
October normally brings us wonderfully autumnal weather and cooling temperatures (although 2/3 of the way through the month the area is running over eight degrees above normal). Average daily highs for October range from 75 on the 1st to 61 on Halloween. Average overnight lows drop from 51 on the 1st to 39 on the 31st. October also continues the precipitation slide into our dry months with 2.48 inches being the long term average for the month. While October snow is rare, the long term average snowfall for the month is one tenth of an inch. What normally is expected in October is our first killing frost. Our long term average first annual freeze is October 22nd. While scattered frost was observed in low lying areas on the morning of the 17th, the official low temperature for that date was 33 so it doesn’t qualify as a killing freeze, although your plants may choose to disagree!