New Forecast Released by NOAA – NBC Chicago

A La Niña Forecast for the Chicago Area

A new La Niña forecast has been released, and it’s causing excitement among weather enthusiasts. But what does it mean for the Chicago area?

According to the National Weather Service’s Climate Prediction Center, La Niña is favored to emerge and is expected to persist through sometime between January and March of 2025, with a 60% chance, a drop from 71% previously.

Signs Point to a "Weak and Short-Duration La Niña"

The latest prediction stresses that signs point to a "weak and short-duration La Niña." So, how could that impact Chicago’s winter?

Chicago’s Winter Forecast: What to Expect

Typically, a La Niña winter places the jet stream in a position to bring overall colder and sometimes snowier patterns during the winter months to the Midwest. The correlation to La Niña and a colder winter in Chicago is greater during a strong La Niña season, but less during a weak La Niña season.

"A weaker La Niña implies that it would be less likely to result in conventional winter impacts, though predictable signals could still influence the forecast guidance," the latest forecast states.

ENSO: El Niño, La Niña, and ENSO-Neutral

ENSO stands for El Niño Southern Oscillation, and the ENSO pattern alternates between El Niño, La Niña, and ENSO-neutral. ENSO-neutral conditions mean neither El Niño nor La Niña patterns are present. Typically, each El Niño or La Niña pattern can last for one or two years.

El Niño emerges when the trade winds near the equator in the Pacific Ocean are out of the west, carrying in warm water across the surface of the Pacific Ocean. A La Niña pattern emerges when the winds shift out of the east, causing upwelling of deep, cool ocean waters to rise to the surface and drift westward.

These alternating patterns ultimately impact the position of the jet stream, and can have global impacts on weather patterns.

Frequently Asked Questions

• Q: What does the forecast say about the strength and duration of La Niña?
  A: The forecast indicates a "weak and short-duration La Niña."
• Q: How likely is La Niña to emerge and persist?
  A: La Niña is favored to emerge and is expected to persist through sometime between January and March of 2025, with a 60% chance.
• Q: What does this mean for the winter forecast in Chicago?
  A: While La Niña is still expected to bring some cold and possibly snowy weather, the impact is likely to be less significant than in a strong La Niña season.
• Q: What’s the current trend in Chicago’s winter weather?
  A: The past few winters have been very mild in Chicago, so an "average" winter would feel colder than recent years.

Conclusion

The National Oceanic and Atmospheric Administration (NOAA) will release its monthly update on our emerging La Niña on October 10. While the forecast remains uncertain, one thing is clear: the Chicago area can expect a potentially cold and snowy winter. Stay tuned for updates and follow NBC Chicago for the latest forecast and weather updates.