Those chilly mornings that we've seen for more than a month are the most unusual thing about this fall's weather ... except for the ongoing drought.
October was the first month in a year with an average temperature that was significantly lower than normal. Most communities in Nebraska and western Iowa averaged October temperatures that were about 2 to 4 degrees lower than normal.
The coldest part of the night occurs at daybreak, and in September and October, temperatures averaged their fourth-lowest on record in Omaha.
“That's not surprising,” said Barbara Mayes, meteorologist with the National Weather Service in Valley. “When the air is dry, it's a little easier to drop down to cool readings at night.”
Dry air holds less moisture, which means it also holds less heat. So on those nights when the skies are clear and winds are still, the daytime heat easily lifts away.
An earlier-than-normal hard freeze was another consequence of those chilly mornings. Omaha had its first hard freeze Oct. 6, about three weeks earlier than normal.
In Iowa, temperatures have averaged below normal for most areas for the past three months, said Harry Hillaker, state climatologist.
“That's a nice change,” he said. “Lower temperatures mean less evaporation.”
Lack of rain added to the deepening drought, except in southeast Nebraska and southwest Iowa, two areas where more abundant rains fell.
Grand Island, which has received 10.7 inches of moisture since last November, is nearly 16 inches below normal, according to the National Weather Service. The city has seen eight consecutive months with below-normal rainfall.
Hillaker said rains across the southern part of Iowa pushed the state to above-normal moisture for the first month since April.
Red Oak had its second-wettest October on record, Hillaker said, with 5.94 inches of rainfall.
Despite the chill and increase in rains, no one is predicting an end to the drought soon. The latest forecast indicates that drought will persist through the winter. Spring rains are the next hope for relief.
Al Dutcher, state climatologist for Nebraska, said he's expecting a roller-coaster type of winter.
“It wouldn't shock me to see a little bit of everything this winter,” he said. “We could see a large fluctuation between above-normal and below-normal temperatures.”
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