This month's miserable cold will carry a footnote as it leaves: record-setting.
In a what has been a colder-than-normal spring, the last half of April has been especially frigid.
In about the past week, 3,318 daily records have been set or matched across the United States for either the coldest night or the coldest day.
In Nebraska, 287 such daily records have been set or matched this month; in Iowa, the number is 172, according to the National Climatic Data Center.
While the weather has been record-setting, it's not unprecedented. For the most part, it's just daily records that are being set, as opposed to new standards for cold for all of April.
Nebraska has set nine monthly records — all in the western half of the state. Iowa hasn't set any monthly records.
Climatologists and meteorologists attribute the unusual cold to:
• A deeply sagging jet stream that allows Arctic air to flow south across the United States, as far south as the Gulf of Mexico.
• Greater-than-usual snow cover across Canada and the northern United States, which allows Arctic air to remain frigid as it flows south. Normally, bare ground saps some of the cold from the air.
• Frequent cloudy days that lessen the warming effect of the sun.
The current warm-up is expected to intensify this weekend, with high temperatures forecast in the 70s to near 80. By the middle of next week, temperatures will drop modestly as another storm system moves through. — Nancy Gaarder