La Niña remains weak, but the phenomenon is still having an impact on Indiana’s weather this winter, according to federal forecasters.
The National Weather Service’s Climate Prediction Center issued an announcement on December 11, predicting that La Niña conditions will remain weak throughout January, which means that Indiana may experience more precipitation and snow than usual. The latest forecast echoes advice issued by the center in November.
The latest report indicates that subsurface ocean temperatures in the Pacific remain below average. Combined with wind anomalies in the same area, this means conditions are consistent with La Niña.
The center predicts a 54% chance of La Niña lasting through December, January and February before transitioning to what forecasters call “ENSO neutral,” meaning neither La Niña nor El Niño will affect the weather.
What is La Niña?
La Niña begins in the central Pacific Ocean. According to the National Weather Service, when ocean temperatures cool, which usually occurs every three to five years, it affects tropical rainfall and, in turn, weather patterns around the world.
These factors combine to push the wave-like jet stream over North America further north into parts of western Canada, causing the storm to curve downward into the Great Lakes region.
How is La Niña affecting Indiana?
As winter storms hit Indiana, precipitation and snowfall rates are likely to increase due to the La Niña effect. El Niño, La Niña’s counterpart, has the opposite effect, making weather drier than normal.
A review of the climatological record of Indiana weather shows that Indiana typically experiences wetter winters during La Niña events, but it is difficult to predict how this will affect temperatures in the state.
Mike Ryan, a meteorologist with the National Weather Service in Indianapolis, said the city’s upcoming winter average temperatures will be “close to below normal.”
Ryan said Indianapolis will likely see a little more than the average 25 inches of snow this winter.
“Precipitation is also expected to be close to or slightly above normal,” Ryan said. “We are expecting a colder December with an increased chance of winter precipitation throughout the first half of the month.”
Indianapolis live weather radar
Indianapolis is expected to see some rain in mid-December after a weekend of snow and freezing temperatures as a weak La Niña pushes Hoosiers into a wet winter.
NWS forecasters predict rising temperatures during the week of December 15, with highs possibly eventually reaching 50 degrees.
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Karl Schneider is IndyStar’s environmental reporter. You can contact him at karl.schneider@indystar.com. Follow him on BlueSky @karlstartswithk.bsky.social or @karlstartswithk.
This article originally appeared in the Indianapolis Star: Will La Niña affect snowfall in Indianapolis this winter? Here’s what you need to know