Peter Finlayson, Ormstown weatherman
The verdict is in for the month of October: warm and wet, and no killing frost yet.
The thermometer dipped to -1 degree C on the night of Friday, October 29 and the ground temperature was recorded at -4.5 C, but the residual heat in the ground seems to have prevented the plants from being put to sleep permanently. It’ll be a few days into November before weather cold enough to officially generate a killing frost is forecast, which will mean the weather event signaling the end of the growing season will be almost a month later than average.
However, killing frost or no, the count for corn heat units (CHU) officially came to an end on October 29. The plants may not have been completely killed but they have become dormant. So, the season, which started on May 10, set a record of 3655 CHU as measured locally over the last 54 years. The heat unit count for October was 325 CHU, over double the normal of 146 CHU, no doubt because there was no killing frost mid-month to bring the count to an end.
The average daily temperatures continued to drop in the last week of the month, so much so that October 2021 will not be the warmest October in the last 54 years as anticipated just a week ago. The average temperature for the first 30 days of the month was 11.8 C, a drop of 1.5 C from the previous week but still well above the normal of 9.4 C for the whole month. October 2021 will likely end up as the third warmest, sitting well behind 2017 at 13.2 C and very close to 1971 at 11.7 C.
And we’ve had enough rain, thank you. The total now stands at 158 mm, which is about twice the normal rainfall for the month. Since October 13, there has been some level of precipitation in 13 out of 17 days, and on October 31 over 30 mm of rain fell in just the one day. Without any warmth, reduced levels of evaporation will keep the fields wet even when the sun returns.
Restarting the corn harvesting is going to be mucky business even if there is no rain in the forecast for the first two weeks of the month. November will continue the October trend with warmer than average nights, but daytime highs will be slightly lower than average, so the month should be about… average!