In regional climate outlooks for the Great Lakes, Missouri basin, and the Midwest, forecasters from NOAA’s Climate Prediction Center expect several potential impacts this winter from the current La Niña pattern in the Pacific Ocean.
From now until early spring, forecasters anticipate La Niña could affect precipitation and temperatures across several central states. The forecasts address the potential for impacts on agriculture, the economy, and ecosystems.
Each region is subject to different repercussions from La Niña. The polar jet stream, which can vary based on La Niña conditions, tends to cut through the Missouri basin, making it the U.S. dividing line between cold and warm air masses. Colder, wetter conditions could be in store for the northern portions of the basin, while the southern Great Plains could be warmer and drier.
Precipitation and temperatures could possibly breakdown as such:
The northern Rockies, Wyoming, the Dakotas, and Great Lakes may experience above-normal precipitation and below-normal temperatures.
Southern areas of Colorado, Wyoming, and Kansas may see slightly increased chances for below-normal precipitation and above-normal temperatures.
La Niña Impacts
Dry soil conditions in the Missouri River basin have already challenged winter wheat, particularly in western Kansas and parts of Wyoming. Lower crop yields and overwintering of pests may develop if predictions for warmer, drier conditions hold true.
Colder spells in the Great Lakes, where a wetter, more frigid winter may develop, could be negative for livestock, driving up farming costs and commodity prices. These factors may contribute to more ice cover as well. Similar conditions could have consequences in the Midwest, where La Niña has the potential to negatively impact fall seeded crops or perennials, such as alfalfa or fruit orchards. Increased costs for heating fuel, snow removal, and transportation are also possible. The northern Rockies could experience above-normal snowpack, which is normally good for water supply later in the year.
Because the La Niña phase is predicted to be weaker and shorter this winter than in previous years, forecasters are assessing the winter with a conservative outlook. It’s likely La Niña’s influence may wane by early spring.
A La Niña develops when temperatures in the equatorial Pacific Ocean are cooler than average for an extended period. This year, the cooling is slight, so there remains a chance the La Niña may not persist. Also, forecasts depend on many variables, such as short-term weather or long-term climate events, that can overshadow the typical La Niña pattern and lessen the reliability of predictions.
To help you better understand how the current La Niña may impact the Midwest and surrounding areas, NOAA releases regional La Niña Outlooks: