A freeze watch is in place Friday evening for Marshalltown and much of Eastern Iowa.

The watch is coming along with below freezing temperatures. The low temperature Friday night is predicted to be 30 degrees, according to the National Weather Service.

“It’s sort of late in the season for a freeze,” said Justin Glison, state climatologist. “Marshalltown has actually had a 32 degree or less reading out to May 29 in 1947.” 

The last time Marshalltown had a recorded temperature on or below 29 degrees was in 1911. 

“It’s not normal behavior, but it’s not extreme,” Glison said. 

The news is worse the further east with possible snow storms predicted in the Northeastern United States and New England. 

“We’re just seeing a dip in the jet stream further south than normal,” Glison said. “It’s allowing colder air to come to us.” 

The freezing temperatures will be prefaced by heavy rainfall on Thursday.

Temperatures will rise during the 50 and 60 degree days, albeit with rain and thunderstorms  predicted this weekend, but the night temperatures will have a cold bite to them. 

Sensitive plants could be affected by a potential freeze and should be covered. 

“We’re not really concerned with stuff that’s been planted already,” Glison said. “We might get some impacts on alfalfa that have already emerged and are growing.” 

Central Iowa will be around the freezing mark, depending on cloud cover. 

“Cloud cover and wind will keep the temperature from going below freezing,” Glison said. “If we’re under a clear sky we could get what’s called radiational cooling and get cooler temperatures.” 

Usually when there’s colder temperatures this late in the year it’s followed by warm weather, he said. 

“You always see a rebound,” Glison said. “Once we get through it we’ll get a warm up.” 

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Contact Thomas Nelson at tnelson@timesrepublican.com