State climatologist talks about December and end of year
January 7th, 2020 by Ric Hanson
(Radio Iowa) — State Climatologist Justin Glisan says the month of December was warmer than average for the second straight year. “We were actually six degrees above average statewide. The average temperature was 28-point-nine degrees,” Glisan says. “It’s interesting — last December 2018 — we were five-point-one degrees above average. So warmer than last year.” The amount of rain and snow in the month was not very notable. “Statewide we were one-point-three-two inches of precipitation — and that’s just two-tenths of an inch below average….we were kind of a balancing act. Northwestern Iowa saw above average precipitation — including snowfall — while southern Iowa and eastern Iowa were below average precipitation wise,” Glisan says.
Glisan says warmer weather had an impact on the normal snow-rain mix of precipitation for December. “Normally in December we get eight-point-three inches of snowfall. Preliminary numbers have us at two-point-four,” according to Glisan. He says the overall average temperature for the year that just ended wasn’t too far from the norm. “Temperature wise we were at 46-point-eight degrees and that ranks us preliminarily as 42nd coldest. We have 147 years of record keeping across the state,” Glisan says. “so, it’s kind of more of a ho-hum year when we are talking temperature wise.” The amount of rain however was in the top ten. “We had 41-point-five-two inches of rainfall plus snowfall — and that makes it the ninth wettest on record — and again these records go back 147 years. You recall back to 2018 — it was actually the second wettest year behind the great flood year of ’93. We had a little over 45 inches last year — with the record being 48 inches in 1993,” Glisan says.
He says the timing of the wet months in 2019 obviously did not work out well in a state that depends on agriculture. “May was the sixth wettest May on record, spring was the 12th wettest. And then we get into dryness concerns moving into July and August. And then we get to September — ninth warmest — 15th wettest,” he says. Glisan says he expects the same type of variable conditions to continue into the new year.
In Atlantic, rain and melted snowfall in December amounted to just .7” (Seven-tenths of an inch). Normally, we would see 1.11 inches. The most precipitation during December happened on the 28th, when we received .6” rain here at the KJAN Studios. The most snow (.6”) fell on the 15th. The average High for last month was nearly 41-degrees (40.9), which was 8-degrees warmer than normal. The warmest (and record-setting) day, was on Christmas Day, when we topped out 60-degrees. The average Low of 20 (19.9), was 5-degrees warmer than normal. Our coldest mornings were on the 17th and 18th, when we bottomed out at 9-degrees both days.
During the month of January, our High in Atlantic is typically around 29 (29.4), and the average Low is 9 (9.3). Precipitation (rain and/or melted snow) is normally around .84” (a little more than ¾ of an inch).