Winter on the Wabash: Forecasters say winter weather will keep its grip on Indiana until at least late March. (Purdue Agricultural Communication photo/Keith Robinson)
Despite that brief sampling of mild weather about a week ago, it looks like winter isn't going away anytime soon. Ken Scheeringa, associate state climatologist for the Indiana State Climate Office based at Purdue University in West Lafayette, says a few days with temperatures in the 50s and 60s might have led us to believe spring is right around the corner, but, he adds, “Not so fast.” And while it isn't abnormal for Hoosiers to see snow and cold linger into mid-March, current weather models suggest spring weather might not move in until even later. "The snow and cold of winter usually continues into the first half of March. Based on the latest weather outlook, it could even persist late into the month," Scheeringa said.
Monthly and seasonal weather outlooks from the Climate Prediction Center show a colder-than-normal, but mostly dry start to March. The cold trend is likely to continue throughout the month, but forecasters are less certain about precipitation later in March.
Moving on to spring, the outlook calls for a slight chance of a colder-than-normal spring in northern Indiana and wetter-than-normal conditions in the southern part of the state.
Early March temperatures in Indiana typically range from 40 degrees in the north to 50 degrees in the south and increase toward the end of the month to a range of mid-50s in the north to the mid-60s in the south. March precipitation normally varies from about 2.5 inches in far northern Indiana to about 4.2 inches in the far southwest.
If winter weather sticks around later than normal, farmers antsy to start planting their corn and soybean crops might have to wait a little bit longer for optimal planting conditions, including soil temperatures of at least 50 degrees at seeding depth.
But according to Purdue Extension corn specialist Bob Nielsen, while a colder March could affect planting dates, the bulk of the state's farmers don't get serious about planting corn until the third week of April. That means weather in early April is likely to influence planting far more heavily than the weather in March.
"The fact that March is colder than normal might or might not impact planting dates, depending on how cold we're talking," he said. "But if we get to a point where it looks like planting might be delayed, it's important to remember that planting date is only one of many factors that influence crop yields."
As an example, Nielsen compared the 2012 cropping year, when farmers planted one of the earliest crops on record before drought decimated yields, with the 2013 cropping year, which started off with delayed planting and ended with above-trendline yields.
In Indiana, the earliest dates farmers can plant corn and still be eligible for crop insurance are April 1 in southern Indiana, April 5 in central and April 10 in northern. Soybean dates are April 15 in southern Indiana, April 20 in central and April 24 in northern. That means farmers have much more time to wait and see how the weather actually plays out.
Forecasters will continue to watch long-range weather models, which Scheeringa said take into account global weather signals, including storm activity in the far west Pacific, surface ocean temperatures and conditions over North America. So far, water temperatures are normal in the Pacific Ocean with a lack of El Niño - a rise in surface water temperatures near the Equator - and La Niña - a drop in surface water temperatures in the same region.
"Neutral El Niño and La Niña ocean patterns are expected to continue as non-players in the spring forecast," Scheeringa said. "But storm activity in the western Pacific should impact the path of the jet stream in the eastern Pacific and over North America. The path would re-establish the old dominant winter pattern of warm conditions in western states and unusual cold east of the Rocky Mountains."